(This document was generated from fetchmail-FAQ.html)
Back to Fetchmail Home Page To Site Map $Date: 1999/09/23 17:21:40 $
_________________________________________________________________
Frequently Asked Questions About Fetchmail
Before reporting any bug, please read G3 for advice on how to include
diagnostic information that will get your bug fixed as quickly as
possible.
If you have a question or answer you think ought to be added to this
FAQ list, mail it to fetchmail's maintainer, Eric S. Raymond, at
esr@snark.thyrsus.com.
General questions:
G1. What is fetchmail and why should I bother?
G2. Where do I find the latest FAQ and fetchmail sources?
G3. I think I've found a bug. Will you fix it?
G4. I have this idea for a neat feature. Will you add it?
G5. Is there a mailing list for exchanging tips?
G6. So, what's this I hear about a fetchmail paper?
G7. What is the best server to use with fetchmail?
G8. How can I avoid sending my password en clair?
G9. Is any special configuration needed to use a dynamic IP address?
G10. Is any special configuration needed to use firewalls?
G11. Is any special configuration needed to send mail?
G12. Is fetchmail Y2K-compliant?
Build-time problems:
B1. Lex bombs out while building the fetchmail lexer.
B2. I get link failures when I try to build fetchmail.
Fetchmail configuration file grammar questions:
F1. Why does my old .fetchmailrc no longer work?
F2. The .fetchmailrc parser won't accept my all-numeric user name.
F3. The .fetchmailrc parser won't accept my host or username beginning
with `no'.
F4. I'm migrating from popclient. How do I need to modify my .poprc?
F5. I'm getting a `parse error' message I don't understand.
Configuration questions:
C1. Why do I need a .fetchmailrc when running as root on my own
machine?
C2. How can I arrange for a fetchmail daemon to get killed when I log
out?
C3. How do I know what interface and address to use with --interface?
C4. How can I set up support for sendmail's anti-spam features?
How to make fetchmail play nice with various MTAs:
T1. How can I use fetchmail with sendmail?
T2. How can I use fetchmail with qmail?
T3. How can I use fetchmail with exim?
T4. How can I use fetchmail with smail?
T5. How can I use fetchmail with SCO's MMDF?
T6. How can I use fetchmail with Lotus Notes?
How to make fetchmail work with various servers:
S1. How can I use fetchmail with qpopper?
S2. How can I use fetchmail with Microsoft Exchange?
S3. How can I use fetchmail with Compuserve RPA?
S4. How can I use fetchmail with Demon Internet's SDPS?
S5. How can I use fetchmail with usa.net's servers?
S6. How can I use fetchmail with HP OpenMail?
S7. How can I use fetchmail with geocities POP3 servers?
S8. How can I use fetchmail with Hotmail?
S9. How can I use fetchmail with MSN?
S10. How can I use fetchmail with SpryNet?
How to set up well-known security and authentication methods:
K1. How can I use fetchmail with SOCKS?
K2. How can I use fetchmail with IPv6 and IPsec?
K3. How can I get fetchmail to work with ssh?
K4. What do I have to do to use the IMAP-GSS protocol?
K5. How can I use fetchmail with SSL?
Runtime fatal errors:
R1. Fetchmail isn't working, and -v shows `SMTP connect failed'
messages.
R2. When I try to configure an MDA, fetchmail doesn't work.
R3. Fetchmail dumps core when given an invalid rc file.
R4. Fetchmail dumps core in -V mode, but operates normally otherwise.
R5. Running fetchmail in daemon mode doesn't work.
R6. Fetchmail hangs when used with pppd.
R7. Fetchmail randomly dies with socket errors.
R8. Fetchmail running as root stopped working after an OS upgrade
R9. Fetchmail is timing out after fetching certain messages but before
deleting them
Disappearing mail
D1. I think I've set up fetchmail correctly, but I'm not getting any
mail.
D2. All my mail seems to disappear after a dropped connection.
D3. Mail that was being fetched when I interrupted my fetchmail seems
to have been vanished.
Multidrop-mode problems:
M1. I've declared local names, but all my multidrop mail is going to
root anyway.
M2. I can't seem to get fetchmail to route to a local domain properly.
M3. I tried to run a mailing list using multidrop, and I have a mail
loop!
M4. My multidrop fetchmail seems to be having DNS problems.
M5. I'm seeing long DNS delays before each message is processed.
M6. How do I get multidrop mode to work with majordomo?
M7. Multidrop mode isn't parsing envelope addresses from my Received
headers as it should.
Mangled mail:
X1. Spurious blank lines are appearing in the headers of fetched mail.
X2. My mail client can't see a Subject line.
X3. Messages containing "From" at start of line are being split.
X4. My mail is being mangled in a new and different way.
X5. Using POP3, retrievals seems to be fetching too much!
Other problems:
O1. The --logfile option doesn't work if the logfile doesn't exist.
O2. Every time I get a POP or IMAP message the header is dumped to all
my terminal sessions.
O3. Does fetchmail reread its rc file every poll cycle?
O4. Why do deleted messages show up again when I take a line hit while
downloading?
O5. Why is fetched mail being logged with my name, not the real From
address?
O6. I'm seeing long sendmail delays or hangs near the start of each
poll cycle.
O7. Why doesn't fetchmail deliver mail in date-sorted order?
O8. I'm using pppd. Why isn't my monitor option working?
Answers:
_________________________________________________________________
G1. What is fetchmail and why should I bother?
Fetchmail is a one-stop solution to the remote mail retrieval problem
for Unix machines, quite useful to anyone with an intermittent PPP or
SLIP connection to a remote mailserver. It can collect mail using any
variant of POP or IMAP and forwards via port 25 to the local SMTP
listener, enabling all the normal forwarding/filtering/aliasing
mechanisms that would apply to local mail or mail arriving via a
full-time TCP/IP connection.
Fetchmail is not a toy or a coder's learning exercise, but an
industrial-strength tool capable of transparently handling every
retrieval demand from those of a simple single-user ISP connection up
to mail retrieval and rerouting for an entire client domain. Fetchmail
is easy to configure, unobtrusive in operation, powerful,
feature-rich, and well documented.
Fetchmail is Open Source software. The openness of the sources is the
strongest assurance of quality you can have. Extensive peer review by
a large, multi-platform user community has shown that fetchmail is as
near bulletproof as the underlying protocols permit.
Fetchmail is licensed under the GNU General Public License.
If you found this FAQ in the distribution, see the README for
fetchmail's full feature list.
_________________________________________________________________
G2. Where do I find the latest FAQ and fetchmail sources?
The latest HTML FAQ is available alongside the latest fetchmail
sources at the fetchmail home page:
http://www.tuxedo.org/~esr/fetchmail. You can also usually find both
in the POP mail tools directory on Sunsite.
A text dump of this FAQ is included in the fetchmail distribution.
Because it freezes at distribution release time, it may not be
completely current.
_________________________________________________________________
G3. I think I've found a bug. Will you fix it?
Yes I will, provided you include enough diagnostic information for me
to go on. Send bugs to fetchmail-friends. When reporting bugs, please
include the following:
1. Your operating system and compiler version.
2. A copy of your POP or IMAP server's greeting line.
3. The name and version of the SMTP listener or MDA you are
forwarding to.
4. Any command-line options you used.
5. The output of fetchmail -V called with whatever other command-line
options you used.
Often, the first thing I will do when you report a bug is tell you to
upgrade to the newest version, and then see if the problem reproduces.
So you'll probably save us both time if you upgrade and test with the
latest version before sending in a bug report.
It is helpful if you include your .fetchmailrc file, but not necessary
unless your symptom seems to involve an error in configuration
parsing. If you do send in your .fetchmailrc, mask the passwords
first!
If fetchmail seems to run and fetch mail, but the headers look mangled
(that is, headers are missing or blank lines are inserted in the
headers) then read the FAQ items in section X before submitting a bug
report. Pay special attention to the item on diagnosing mail mangling.
There are lots of ways for other programs in the mail chain to screw
up that look like fetchmail's fault, but you may be able to fix these
by tweaking your configuration.
A transcript of the failed session with -v -v (yes, that's two -v
options, enabling debug mode) will almost always be useful. It is very
important that the transcript include your POP/IMAP server's greeting
line, so I can identify it in case of server problems. This transcript
will not reveal your passwords, which are specially masked out
precisely so the transcript can be passed around.
If the bug involves a core dump or hang, a gdb stack trace is good to
have. (Bear in mind that you can attach gdb to a running but hung
process by giving the process ID as a second argument.) You will need
to reconfigure with
CFLAGS=-g LDFLAGS=" " ./configure
and then rebuild in order to generate a version that can be
gdb-traced.
Best of all is a mail file which, when fetched, will reproduce the bug
under the latest (current) version.
Any bug I can reproduce will usually get fixed very quickly, often
within 48 hours. Bugs I can't reproduce are a crapshoot. If the
solution isn't obvious when I first look, it may evade me for a long
time (or to put it another way, fetchmail is well enough tested that
the easy bugs have long since been found). So if you want your bug
fixed rapidly, it is not just sufficient but nearly necessary that you
give me a way to reproduce it.
_________________________________________________________________
G4. I have this idea for a neat feature. Will you add it?
Probably not. Most of the feature suggestions I get are for ways to
set various kinds of administrative policy or add more spam filtering
(the most common one, which I used to get about four million times a
week and got really tired of, is for tin-like kill files).
You can do spam filtering better with procmail or maildrop on the
server side and (if you're the server sysadmin) sendmail.cf domain
exclusions. You can do other policy things better with the mda option
and script wrappers around fetchmail. If it's a
prime-time-vs.-non-prime-time issue, ask yourself whether a wrapper
script called from crontab would do the job.
I'm not going to do these; fetchmail's job is transport, not policy,
and I refuse to change it from doing one thing well to attempting many
things badly. One of my objectives is to keep fetchmail simple so it
stays reliable.
Furthermore, since about version 4.3.0 fetchmail has passed out of
active development and been essentially stable. It is no longer my top
project, and I am going to be quite reluctant to add features that
might either jeopardize its stability or involve me in large amounts
of coding.
All that said, if you have a feature idea that really is about a
transport problem that can't be handled anywhere but fetchmail, lay it
on me. I'm very accommodating about good ideas.
_________________________________________________________________
G5. Is there a mailing list for exchanging tips?
There is a fetchmail-friends list for people who want to discuss fixes
and improvements in fetchmail and help co-develop it. It's at
fetchmail-friends@thyrsus.com. There is also an announcements-only
list, fetchmail-announce@thyrsus.com.
Both lists are SmartList reflectors; sign up in the usual way with a
message containing the word "subscribe" in the subject line sent to
fetchmail-friends-request@thyrsus.com or
fetchmail-announce-request@thyrsus.com. (Similarly, "unsubscribe" in
the Subject line unsubscribes you, and "help" returns general list
help)
_________________________________________________________________
G6. So, what's this I hear about a fetchmail paper?
The fetchmail development was also a sociological experiment, an
extended test to see if my theory about the critical features of the
Linux development model is correct.
The experiment was a success. I wrote a paper about it titled The
Cathedral and the Bazaar which was first presented at Linux Kongress
'97 in Bavaria and very well received there. It was also given at
Atlanta Linux Expo, Linux Pro '97 in Warsaw, and the first Perl
Conference, at UniForum '98, and was the basis of an invited
presentation at Usenix '98. The folks at Netscape tell me it helped
them decide to give away the source for Netscape Communicator.
If you're reading a non-HTML dump of this FAQ, you can find the paper
on the Web with a search for that title.
_________________________________________________________________
G7. What is the best server to use with fetchmail?
The short answer: IMAP4rev1 running over Unix.
Here's a longer answer:
Fetchmail will work with any POP, IMAP, or ESMTP/ETRN server that
conforms to the relevant RFCs (and even some outright broken ones like
Microsoft Exchange). This doesn't mean it works equally well with all,
however. POP2 servers, and POP3 servers without LAST, limit
fetchmail's capabilities in various ways described on the manual page.
Most modern Unixes (and effectively all Linux/*BSD systems) come with
POP3 support preconfigured (but beware of the horribly broken POP3
server mentioned in D2). An increasing minority also feature IMAP (you
can detect IMAP support by running fetchmail in AUTO mode, or by using
the `Probe for a server' function in the fetchmailconf utility).
If you have the option, we recommend using or installing an IMAP4rev1
server; it has the best facilities for tracking message `seen' states.
It also recovers from interrupted connections more gracefully than
POP3, and enables some significant performance optimizations.
Don't be fooled by NT/Exchange propaganda. M$ Exchange is just plain
broken (see item S2) and NT cannot handle the sustained load of a
high-volume remote mail server. Even Microsoft itself knows better
than to try this; their own Hotmail service runs over Solaris! For
extended discussion, see John Kirch's excellent white paper on Unix
vs. NT performance.
You can find sources for IMAP software at The IMAP Connection; we like
the open-source UW IMAP server, which is the reference implementation
of IMAP. UW IMAP's support for GSSAPI gives you a good way to
authenticate without sending a password en clair.
Source for a high-quality supported implementation of POP is available
from the Eudora FTP site. Don't use 2.5, which has a rather
restrictive license. The 2.5.2 version appears to restore the
open-source license of previous versions.
_________________________________________________________________
G8. How can I avoid sending my password en clair?
Depending on what your mail server you are talking to, this ranges
from trivial to impossible. It may even be next to useless.
Most people use fetchmail over phone wires, which are hard to tap.
Anybody with the skill and resources to do this could get into your
server mailbox with much less effort by subverting the server host. So
if your provider setup is modem wires going straight into a service
box, you probably don't need to worry.
In general there is little point in trying to secure your fetchmail
transaction unless you trust the security of the server host you are
retrieving mail from. Your vulnerability is more likely to be an
insecure local network on the server end (e.g. to somebody with a
TCP/IP packet sniffer intercepting Ethernet traffic between the modem
concentrator you dial in to and the mailserver host).
Having realized this, you need to ask whether password encryption
alone will really address your security exposure. If you think you
might be snooped, it's better to use end-to-end encryption on your
whole mail stream so none of it can be read. One of the advantages of
fetchmail over conventional SMTP-push delivery is that you may be able
to arrange this by using ssh(1); see K3.
If ssh/sshd isn't available, or you find it too complicated for you to
set up, password encryption will at least keep a malicious cracker
from deleting your mail, and require him to either tap your connection
continuously or crack root on the server in order to read it.
You can deduce what encryptions your mail server has available by
looking at the server greeting line (and, for IMAP, the response to a
CAPABILITY query). Do a fetchmail -v to see these, or telnet direct to
the server port (110 for POP3, 143 for IMAP).
The facility you are most likely to have available is APOP. This is a
POP3 feature supported by many servers (fetchmailconf's autoprobe
facility will detect it and tell you if you have it). If you see
something in the greeting line that looks like an
angle-bracket-enclosed Internet address with a numeric left-hand part,
that's an APOP challenge (it will vary each time you log in). You can
register a secret on the host (using popauth(8) or some program like
it). Specify the secret as your password in your .fetchmailrc; it will
be used to encrypt the current challenge, and the encrypted form will
be sent back the the server for verification.
Alternatively, you may have Kerberos available. This may require you
to set up some magic files in your home directory on your client
machine, but means you can omit specifying any password at all.
Fetchmail supports two different Kerberos schemes. One is a POP3
variant called KPOP; consult the documentation of your mail server to
see if you have it (one clue is the string "krb-IV" in the greeting
line on port 110). The other is an IMAP facility described by RFC1731.
You can tell if this one is present by looking for AUTH=KERBEROS_V4 in
the CAPABILITY response.
If you are fetching mail from a CompuServe POP3 account, you can use
their RPA authentication (which works much like APOP). See S3 for
details.
Your POP3 server may have the RFC1938 OTP capability to use one-time
passwords (if it doesn't, you can get OTP patches for the 2.2 version
of the Qualcomm popper from Craig Metz). To check this, look for the
string "otp-" in the greeting line. If you see it, and your fetchmail
was built with OPIE support compiled in (see the distribution INSTALL
file), fetchmail will detect it also. When using OTP, you will specify
a password but it will not be sent en clair.
Sadly, there is at present (July 1998) no OTP or APOP-like facility
generally available on IMAP servers. However, there do exist patches
which will OTP-enable the University of Washington IMAP daemon,
version 4.2-FINAL. And we have a report that the GSSAPI support in
fetchmail works with the GSSAPI support in the most recent version of
UW IMAP.
You can get both POP3 and IMAP OTP patches from Craig Metz, over FTP
via either ftp://ftp.inner.net/pub/opie/patches (IPv4) or
ftp://ftp.ipv6.inner.net/pub/opie/patches (IPv6).
These patches use a SASL authentication method named "X-OTP" because
there is not currently a standard way to do this; fetchmail also uses
this method, so the two will interoperate happily. They better,
because this is how Craig gets his mail ;-)
(One important win of OTP is that it's not subject to EAR
restrictions.)
_________________________________________________________________
G9. Is any special configuration needed to use a dynamic IP address?
Yes. In order to avoid giving indigestion to certain picky MTAs
(notably exim), fetchmail always makes the RCPT TO address it feeds
the MTA a fully qualified one with a hostname part. Normally it does
this by appending @ and "localhost", but when you are using Kerberos
or ETRN mode it will append @ and your machine's fully-qualified
domain name (FQDN).
Appending the FQDN can create problems when fetchmail is running in
daemon mode and outlasts the dynamic IP address assignment your client
machine had when it started up.
Since the new IP address (looked up at RCPT TO interpretation time)
doesn't match the original, the most benign possible result is that
your MTA thinks it's seeing a relaying attempt and refuses. More
frequently, fetchmail will try to connect to a nonexistent host
address and time out. Worst case, you could up forwarding your mail to
the wrong machine!
Use the smtpaddress option to force the appended hostname to one with
a (fixed) IP address of 127.0.0.1 in your /etc/hosts. (The name
`localhost' will usually work; or you can use the IP address itself).
Only one fetchmail option interacts directly with your IP address,
`interface'. This option can be used to set the gateway device and
restrict the IP address range fetchmail will use. Such a restriction
is sometimes useful for security reasons, especially on multihomed
sites. See C3.
I recommend against trying to set up the interface option when
initially developing your poll configuration -- it's never necessary
to do this just to get a link working. Get the link working first,
observe the actual address range you see on connections, and add an
interface option (if you need one) later.
If you're using a dynamic-IP configuration, one other (non-fetchmail)
problem you may run into with outgoing mail is that some sites will
bounce your email because the hostname your giving them isn't real
(and doesn't match what they get doing a reverse DNS on your
dynamically-assigned IP address). If this happens, you need to hack
your sendmail so it masquerades as your host. Setting
DMsmarthost.here
in your sendmail.cf will work, or you can set
MASQUERADE_AS(smarthost.here)
in the m4 configuration and do a reconfigure. (In both cases, replace
smarthost.here with the actual name of your mailhost.) See the
sendmail FAQ for more details.
_________________________________________________________________
G10. Is any special configuration needed to use firewalls?
No. You can use fetchmail with SOCKS, the standard tool for
indirecting TCP/IP through a firewall. You can find out about SOCKS,
and download the SOCKS software including server and client code, at
the SOCKS distribution site.
The specific recipe for using fetchmail with a firewall is at K1
_________________________________________________________________
B1. Lex bombs out while building the fetchmail lexer.
In the immortal words of Alan Cox the last time this came up: ``Take
the Solaris lex and stick it up the backside of a passing Sun
salesman, then install flex and use that. All will be happier.''
I couldn't have put it better myself, and ain't going to try now.
_________________________________________________________________
G11. Is any special configuration needed to send mail?
A user asks: but how do we send mail out to the POP3 server? Do I need
to implement another tool or will fetchmail do this too?
Fetchmail only handles the receiving side. The sendmail or other
preinstalled MTA on your client machine will handle sending mail
automatically; it will ship mail that is submitted while the
connection is active, and put mail that is submitted while the
connection is inactive into the outgoing queue.
Normally, sendmail is also run periodically (every 15 minutes on most
Linux systems) in a mode that tries to ship all the mail in the
outgoing queue. If you have set up something like pppd to
automatically dial out when your kernel is called to open a TCP/IP
connection, this will ensure that the mail gets out.
_________________________________________________________________
G12. Is fetchmail Y2K-compliant?
Fetchmail is fully Y2K-compliant.
Fetchmail could theoretically have problems when the 32-bit time_t's
roll over in 2038, but I doubt it. Timestamps aren't used for anything
but log entry generation.
_________________________________________________________________
B2. I get link failures when I try to build fetchmail.
If you get errors resembling these
mxget.o(.text+0x35): undefined referenceto `__res_search'
mxget.o(.text+0x99): undefined reference to`__dn_skipname'
mxget.o(.text+0x11c): undefined reference to`__dn_expand'
mxget.o(.text+0x187): undefined reference to`__dn_expand'
make: *** [fetchmail] Error 1
then you must add "-lresolv" to the LOADLIBS line in your Makefile
once you have installed the `bind' package.
_________________________________________________________________
F1. Why does my old .fetchmailrc file no longer work?
If your file predates 5.0.9
In 5.0.9, the auth keyword and option were changed to preauth.
If your file predates 4.5.5
If the dns option is on (the default), you may need to make sure that
any hostname you specify (for mail hosts or for an SMTP target) is a
canonical fully-qualified hostname). In order to avoid DNS overhead
and complications, fetchmail no longer tries to derive the fetchmail
client machine's canonical DNS name at startup.
If your file predates 4.0.6:
Just after the `via' option was introduced, I realized that the
interactions between the `via', `aka', and `localdomains' options were
out of control. Their behavior had become complex and confusing, so
much so that I was no longer sure I understood it myself. Users were
being unpleasantly surprised.
Rather than add more options or crock the code, I re-thought it. The
redesign simplified the code and made the options more orthogonal, but
may have broken some complex multidrop configurations. Any multidrop
configurations that depended on the name just after the `poll' or
`skip' keyword being still interpreted as a DNS name for
address-matching purposes, even in the presence of a `via' option,
will break.
It is theoretically possible that other unusual configurations (such
as those using a non-FQDN poll name to generate Kerberos IV tickets)
might also break; the old behavior was sufficiently murky that we
can't be sure. If you think this has happened to you, contact the
maintainer.
If your file predates 3.9.5:
The `remote' keyword has been changed to `folder'. If you try to use
the old keyword, the parser will utter a warning.
If your file predates 3.9:
It could be because you're using a .fetchmailrc that's written in the
old popclient syntax without an explicit `username' keyword leading
the first user entry attached to a server entry. This error can be
triggered by having a user option such as `keep' or `fetchall' before
the first explicit username. For example, if you write
poll openmail protocol pop3
keep user "Hal DeVore" there is hdevore here
the `keep' option will generate an entire user entry with the default
username (the name of fetchmail's invoking user).
The popclient compatibility syntax was removed in 4.0. It complicated
the configuration file grammar and confused users.
If your file predates 2.8:
The `interface', `monitor' and `batchlimit' options changed after 2.8.
They used to be global options with `set' syntax like the batchlimit
and logfile options. Now they're per-server options, like `protocol'.
If you had something like
set interface = "sl0/10.0.2.15"
in your .fetchmailrc file, simply delete that line and insert
`interface sl0/10.0.2.15' in the server options part of your
`defaults' declaration.
Do similarly for any `monitor' or `batchlimit' options.
_________________________________________________________________
F2. The .fetchmailrc parser won't accept my all-numeric user name.
Either upgrade to a post-5.0.5 fetchmail or put string quotes around
it. :-)
The configuration file parser in older fetchmail versions treated any
all-numeric token as a number, which confused it when it was expecting
a name. String quoting forces the token's class.
The lexical analyzer in 5.0.6 and beyond is smarter and assumes any
token following "username" or "password" is a string.
_________________________________________________________________
F3. The .fetchmailrc parser won't accept my host or username beginning with
`no'.
See F2 You're caught in an unfortunate crack between the newer-style
syntax for negated options (`no keep', `no rewrite' etc.) and the
older style run-on syntax (`nokeep', `norewrite' etc.).
Upgrade to a 5.0.6 or later fetchmail, or put string quotes around
your token.
_________________________________________________________________
F4. I'm migrating from popclient. How do I need to modify my .poprc?
If you have been using popclient (the ancestor of this program) at
version 3.0b6 or later, start with this
(cd; mv .poprc .fetchmailrc)
and do fetchmail -V to see if fetchmail's parser understands your
configuration.
Be aware that some of popclient's unnecessary options have been
removed (see the NOTES file in the distribution for explanation). You
can't deliver to a local mail file or to standard output any more, and
using an MDA for delivery is discouraged. If you throw those options
away, fetchmail will now forward your mail into your system's normal
Internet-mail delivery path.
Actually, using an MDA is now almost always the wrong thing; the MDA
facility has been retained only for people who can't or won't run a
sendmail-like SMTP listener on port 25. The default, SMTP forwarding
to port 25, is better for at least three major reasons. One: it feeds
retrieved POP and IMAP mail into your system's normal delivery path
along with local mail and normal Internet mail, so all your normal
filtering/aliasing/forwarding setup for local mail works. Two: because
the port 25 listener returns a positive acknowledge, fetchmail can be
sure you're not going to lose mail to a disk-full or some other
resource-exhaustion problem. Three: it means fetchmail doesn't have to
know where the system mailboxes are, or futz with file locking (which
makes two fewer places for it to potentially mess up).
If you used to use -mda "procmail -d <you>" or something similar,
forward to port 25 and do "| procmail -d <you>" in your ~/.forward
file.
As long as your new .fetchmailrc file does not use the removed
`localfolder' option or `limit' (which now takes a maximum byte size
rather than a line count), a straight move or copy of your .poprc will
often work. (The new run control file syntax also has to be a little
stricter about the order of options than the old, in order to support
multiple user descriptions per server; thus you may have to rearrange
things a bit.)
Run control files in the minimal .poprc format (without the `username'
token) will trigger a warning. To eliminate this warning, add the
`username' keyword before your first user entry per server (it is
already required before second and subsequent user entries per server.
In some future version the `username' keyword will be required.
_________________________________________________________________
F5. I'm getting a `parse error' message I don't understand.
The most common cause of mysterious parse errors is putting a server
option after a user option. Check the manual page; you'll probably
find that by moving one or more options closer to the `poll' keyword
you can eliminate the problem.
Yes, I know these ordering restrictions are hard to understand.
Unfortunately, they're necessary in order to allow the `defaults'
feature to work.
_________________________________________________________________
C1. Why do I need a .fetchmailrc when running as root on my own machine?
Ian T. Zimmerman <itz@rahul.net> asked:
On the machine where I'm the only real user, I run fetchmail as root
from a cron job, like this:
fetchmail -u "itz" -p POP3 -s bolero.rahul.net
This used to work as is (with no .fetchmailrc file in root's home
directory) with the last version I had (1.7 or 1.8, I don't remember).
But with 2.0, it RECPs all mail to the local root user, unless I
create a .fetchmailrc in root's home directory containing:
skip bolero.rahul.net proto POP3
user itz is itz
It won't work if the second line is just "user itz". This is silly.
It seems fetchmail decides to RECP the `default local user' (i.e. the
uid running fetchmail) unless there are local aliases, and the
`default' aliases (itz->itz) don't count. They should.
Answer:
No they shouldn't. I thought about this for a while, and I don't much
like the conclusion I reached, but it's unavoidable. The problem is
that fetchmail has no way to know, in general, that a local user `itz'
actually exists.
"Ah!" you say, "Why doesn't it check the password file to see if the
remote name matches a local one?" Well, there are two reasons.
One: it's not always possible. Suppose you have an SMTP host declared
that's not the machine fetchmail is running on? You lose.
Two: How do you know server itz and SMTP-host itz are the same person?
They might not be, and fetchmail shouldn't assume they are unless
local-itz can explicitly produce credentials to prove it (that is, the
server-itz password in local-itz's .fetchmailrc file.).
Once you start running down possible failure modes and thinking about
ways to tinker with the mapping rules, you'll quickly find that all
the alternatives to the present default are worse or unacceptably more
complicated or both.
_________________________________________________________________
C2. How can I arrange for a fetchmail daemon to get killed when I log out?
The easiest way to dispatch fetchmail on logout (which will work
reliably only if you have just one login going at any time) is to
arrange for the command `fetchmail -q' to be called on logout. Under
bash, you can arrange this by putting `fetchmail -q' in the file
`~/.bash_logout'. Most csh variants execute `~/.logout' on logout. For
other shells, consult your shell manual page.
Automatic startup/shutdown of fetchmail is a little harder to arrange
if you may have multiple login sessions going. In the contrib
subdirectory of the fetchmail distribution there is some shell code
you can add to your .bash_login and .bash_logout profiles that will
accomplish this. Thank James Laferriere <babydr@nwrain.net> for it.
Some people start up and shut down fetchmail using the ppp-up and
ppp-down scripts of pppd.
_________________________________________________________________
C3. How do I know what interface and address to use with --interface?
This depends a lot on your local networking configuration (and right
now you can't use it at all except under Linux). However, here are
some important rules of thumb that can help. If they don't work, ask
your local sysop or your Internet provider.
First, you may not need to use --interface at all. If your machine
only ever does SLIP or PPP to one provider, it's almost certainly by a
point to point modem connection to your provider's local subnet that's
pretty secure against snooping (unless someone can tap your phone or
the provider's local subnet!). Under these circumstances, specifying
an interface address is fairly pointless.
What the option is really for is sites that use more than one
provider. Under these circumstances, typically one of your provider IP
addresses is your mailserver (reachable fairly securely via the modem
and provider's subnet) but the others might ship your packets
(including your password) over unknown portions of the general
Internet that could be vulnerable to snooping. What you'll use
--interface for is to make sure your password only goes over the one
secure link.
To determine the device:
1. If you're using a SLIP link, the correct device is probably sl0.
2. If you're using a PPP link, the correct device is probably ppp0.
3. If you're using a direct connection over a local network such as
an ethernet, use the command `netstat -r' to look at your routing
table. Try to match your mailserver name to a destination entry;
if you don't see it in the first column, use the `default' entry.
The device name will be in the rightmost column.
To determine the address and netmask:
1. If you're talking to slirp, the correct address is probably
10.0.2.15, with no netmask specified. (It's possible to configure
slirp to present other addresses, but that's the default.)
2. If you have a static IP address, run `ifconfig <device>', where
<device> is whichever one you've determined. Use the IP address
given after "inet addr:". That is the IP address for your end of
the link, and is what you need. You won't need to specify a
netmask.
3. If you have a dynamic IP address, your connection IP will vary
randomly over some given range (that is, some number of the least
significant bits change from connection to connection). You need
to declare an address with the variable bits zero and a
complementary netmask that sets the range.
To illustrate the rule for dynamic IP addresses, let's suppose you're
hooked up via SLIP and your IP provider tells you that the dynamic
address pool is 255 addresses ranging from 205.164.136.1 to
205.164.136.255. Then
interface "sl0/205.164.136.0/255.255.255.0"
would work. To range over any value of the last two octets (65536
addresses) you would use
interface "sl0/205.164.0.0/255.255.0.0"
_________________________________________________________________
C4. How can I set up support for sendmail's anti-spam features?
This answer covers versions of sendmail from 8.8.7 (the version
installed in Red Hat 5.1) upwards. If you have an older version,
upgrade to sendmail 8.9.
Stock sendmails can now do anti-spam exclusions based on a database of
filter rules. The human-readable form of the database is at
/etc/mail/deny. The database itself is at /etc/mail/deny.db.
The table itself uses email addresses, domain names, and network
numbers as keys. For example,
spammer@aol.com REJECT
cyberspammer.com REJECT
192.168.212 REJECT
would refuse mail from spammer@aol.com, any user from cyberspammer.com
(or any host within the cyberspammer.com domain), and any host on the
192.168.212.* network. (This feature can be used to do other things as
well; see the sendmail documentation for details)
To actually set up the database, run
makemap hash deny <deny
in /etc/mail.
To test, send a message to your mailing address from that host and
then pop off the message with fetchmail, using the -v argument. You
can monitor the SMTP transaction, and when the FROM address is parsed,
if sendmail sees that it is an address in spamlist, fetchmail will
flush and delete it.
Under no circumstances put your mailhost or any host you accept mail
from using fetchmail into your reject file. You will lose mail if you
do this!!!
_________________________________________________________________
T1. How can I use fetchmail with sendmail?
For most sendmails, no special configuration is required. Eric Allman
tells me that if FEATURE(always_add_domain) is included in sendmail's
configuration, you can leave the rewrite option off.
If your sendmail complains ``sendmail does not relay'', make sure your
sendmail,cf file says Cwlocalhost so that sendmail recognizes
`localhost' as a name of its host.
If you're mailing from another machine on your local network, also
ensure that its IP address is listed in ip_allow or name in name_allow
(usually in /etc/mail/)
If you find that your sendmail doesn't like the address
`FETCHMAIL-DAEMON@localhost' (which is used in the bouncemail that
fetchmail generates), you may have to set
FEATURE(accept_unqualified_senders).
Günther Leber reports that Digital Unix sendmails won't work with
fetchmail. The symptom is an error message "553 Local configuration
error, hostname not recognized as local". The problem is that
fetchmail normally feeds sendmail with the client machine's host
address in the MAIL FROM line. These sendmails think this means
they're seeing the result of a mail loop and suppress the mail. You
may be able to work around this by running in --invisible mode.
If you want to support multidrop mode, and you can get access to your
mailserver's sendmail.cf file, it's a good idea to add this rule:
H?l?Delivered-To: $u
and declare `envelope "Delivered-To:"'. This will cause the
mailserver's sendmail to reliably write the appropriate envelope
address into each message before fetchmail sees it, and tell fetchmail
which header it is. With this change, multidrop mode should work
reliably even when the Received header omits the envelope address
(which will typically be the case when the message has multiple
recipients).
_________________________________________________________________
T2. How can I use fetchmail with qmail?
Turn on the forcecr option; qmail's listener mode doesn't like header
or message lines terminated with bare linefeeds.
(This information is thanks to Robert de Bath
<robert@mayday.cix.co.uk>.)
If a mailhost is using the qmail package (see
http://pobox.com/~djb/qmail.html) then, providing the local hosts are
also using qmail, it is possible to set up one fetchmail link to be
reliably collect the mail for an entire domain.
One of the basic features of qmail is the `Delivered-To:' message
header. Whenever qmail delivers a message to a local mailbox it puts
the username and hostname of the envelope recipient on this line. The
major reason for this is to prevent mail loops.
To set up qmail to batch mail for a disconnected site the ISP-mailhost
will have normally put that site in its `virtualhosts' control file so
it will add a prefix to all mail addresses for this site. This results
in mail sent to 'username@userhost.userdom.dom.com' having a
'Delivered-To:' line of the form:
Delivered-To: mbox-userstr-username@userhost.userdom.dom.com
A single host maildrop will be slightly simpler:
Delivered-To: mbox-userstr-username@userhost.dom.com
The ISP can make the 'mbox-userstr-' prefix anything they choose but a
string matching the user host name is likely.
To use this line you must:
1. Ensure the option `envelope Delivered-To:' is in the fetchmail
config file.
2. Ensure you have a localdomains containing 'userdom.dom.com' or
`userhost.dom.com' respectively.
So far this reliably delivers messages to the correct machine of the
local network, to deliver to the correct user the 'mbox-userstr-'
prefix must be stripped off of the user name. This can be done by
setting up an alias within the qmail MTA on each local machine. Simply
create a dot-qmail file called '.qmail-mbox-userstr-default' in the
alias directory (normally /var/qmail/alias) with the contents:
| ../bin/qmail-inject -a -f"$SENDER" "${LOCAL#mbox-userstr-}@$HOST"
Note this does require a modern /bin/sh.
Peter Wilson adds:
``My ISP uses "alias-unzzippedcom-" as the prefix, which means that I
need to name my file ".qmail-unzzippedcom-default". This is due to
qmail's assumption that a message sent to user-xyz is handled by the
file ~user/.qmail-xyz (or ~user/.qmail-default).''
Luca Olivetti adds:
If you aren't using qmail locally, or you don't want to set up the
alias mechanism described above, you can use the option `qvirtual
"mbox-userstr-"' in your fetchmail config file to strip the prefix
from the local user name.
_________________________________________________________________
T3. How can I use fetchmail with exim?
If you have rewrite on:
There is an RFC1123 requirement that MAIL FROM and RCPT TO addresses
you pass to it have to be canonical (e.g. with a fully qualified
hostname part). Therefore fetchmail tries to pass fully qualified RCPT
TO addresses. But exim does not by default accept `localhost' as a
fully qualified domain. This can be fixed.
In exim.conf, add `localhost' to your local_domains declaration if
it's not already present. For example, the author's site at
thyrsus.com would have a line reading:
local_domains = thyrsus.com:localhost
If you have rewrite off:
MAIL FROM is a potential problem if the MTAs upstream from your
fetchmail don't necessarily pass canonicalized From and Return-Path
addresses, and fetchmail's rewrite option is off. The specific case
where this has come up involves bounce messages generated by sendmail
on your mailer host, which have the (un-canonicalized) origin address
MAILER-DAEMON.
The right way to fix this is to enable the rewrite option and have
fetchmail canonicalize From and Return-Path addresses with the
mailserver hostname before exim sees them. This option is enabled by
default, so it won't be off unless you turned it off.
If you must run with rewrite off, there is a switch in exim's
configuration files that allows it to accept domainless MAIL FROM
addresses; you will have to flip it by putting the line
sender_unqualified_hosts = localhost
in the main section of the exim configuration file. Note that this
will result in such messages having an incorrect domain name attached
to their return address (your SMTP listener's hostname rather than
that of the remote mail server).
_________________________________________________________________
T4. How can I use fetchmail with smail?
Smail 3.2 is very nearly plug-compatible with sendmail, and may work
fine out of the box.
We have one report that when processing multiple messages from a
single fetchmail session, smail sometimes delivers them in an order
other than received-date order. This can be annoying because it
scrambles conversational threads. This is not fetchmail's problem, it
is an smail `feature' and has been reported to the maintainers as a
bug.
Very recent smail versions require an -smtp_hello_verify option in the
smail config file. This overrides smail's check to see that the HELO
address is actually that of the client machine, which is never going
to be the case when fetchmail is in the picture. According to RFC1123
an SMTP listener must allow this mismatch, so smail's new behavior
(introduced sometime between 3.2.0.90 and 3.2.0.95) is a bug.
_________________________________________________________________
T5. How can I use fetchmail with SCO's MMDF?
MMDF itself is difficult to configure, but it turns out that
connecting fetchmail to MMDF's SMTP channel isn't that hard. You can
read an MMDF recipe that describes replacing a UUCP link with
fetchmail feeding MMDF.
_________________________________________________________________
T6. How can I use fetchmail with Lotus Notes?
The Lotus Notes SMTP gateway tries to deduce when it should convert \n
to \r\n, but its rules are not the intuitive and correct-for-RFC822
ones. Use `forcecr'.
_________________________________________________________________
S1. How can I use fetchmail with qpopper?
Qualcomm's qpopper is probably the best-of-breed among POP3 servers,
and is very widely deployed. Nevertheless, it has some problems which
fetchmail exposes. We recommend using IMAP instead if at all possible.
If you must talk to qpopper, here are some problems to be aware of:
Problems with retrieving large messages from qpopper 2.53
Tony Tang <tyw@atnhk.com> reports that there is a bad intercation
between fetchmail and qpopper 2.5.3 under Red Hat Linux versions 5.0
to 5.2, kernels 2.0.34 to 2.0.35. When fetching very large messages
(over 700K) from 2.5.3, fetchmail will hang with a socket error.
This is probably not a fetchmail bug, but rather a symptom of some
problem in the networking stack that qpopper's transmission pattern is
tickling, as fetchpop (another Linux POP client) also displays the
hang but Netscape running under Win95 does not. The problem can also
be banished by upgrading to qpopper 3.0b1.
Bad interaction with fetchmail 4.4.2 to 4,4.7
Versions of fetchmail from 4.4.2 through 4.4.7 had a bad interaction
with Eudora qpopper versions 2.3 and later. See X5 for details. The
solution is to upgrade your fetchmail.
_________________________________________________________________
S2. How can I use fetchmail with Microsoft Exchange?
Fetchmail now supports the proprietary NTLM mode used with M$ Exchange
servers. To enable this, configure fetchmail with the --enable-NTLM
option and recompile it.
M$ Exchange violates the POP3 RFCs. Its LIST command does not reveal
the real sizes of mail in the pop mailbox, but the sizes of the
compressed versions in the exchange mail database (thanks to Arjan De
Vet and Guido Van Rooij for alerting us to this problem).
Fetchmail works with M$ Exchange, despite this brain damage. Two
features are compromised. One is that the --limit option will not work
right (it will check against compressed and not actual sizes). The
other is that a too-small SIZE argument may be passed to your ESMTP
listener, assuming you're using one (this should not be a problem
unless the actual size of the message is above the listener's
configured length limit).
Somewhat belatedly, I've learned that there's supposed to be a
registry bit that can fix this breakage:
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\MsExchangeIs\Parameters
System\Pop3 Compatibility
This is a bitmask that controls the variations from the standard
protocol. The bits defined are:
0x00000001:
Report exact message sizes for the LIST command
0x00000002:
Allow arbitrary linear whitespace between commands and
arguments
0x00000004:
Enable the LAST command
0x00000008:
Allow an empty PASS command (needed for users with blank
passwords, but illegal in the protocol)
0x00000010:
Relax the length restrictions for arguments to commands
(protocol requires 40, but some user names may be longer than
that).
0x00000020:
Allow spaces in the argument to the USER command.
There's another one that may be useful to know about:
KEY_LOCAL_MACHINE\System\CurrentControlSet\Services\MsExchangeIs\Parameters
System\Pop3 Performance
0x00000001:
Render messages to a temporary stream instead of sending
directly from the database (should always be on)
0x00000002: Flag unrenderable messages (instead of just failing
commands) (should only be on if you are seeing the problems
reported in KB Q168109)
0x00000004:
Return from the QUIT command before all messages have been
deleted.
The Microsoft pod-person who revealed this information to me admitted
that he couldn't find it anywhere in their public knowledge base.
You can mess with these bits. Or, better yet, you can lose that
brain-dead Microsoft crap and install a real operating system on your
mailserver.
_________________________________________________________________
S3. How can I use fetchmail with CompuServe RPA?
First, make sure your fetchmail has the RPA support compiled in. Stock
fetchmail binaries (such as you might get from an RPM) don't. You can
check this by looking at the output of fetchmail -V; if you see the
string "+RPA" after the version ID you're good to go, otherwise you'll
have to build your own from sources (see the INSTALL file in the
source distribution for directions).
Give your CompuServe pass-phrase in lower case as your password. Add
`@compuserve.com' to your user ID so that it looks like `user
<UserID>@compuserve.com', where <UserID> can be either your numerical
userID or your E-mail nickname. An RPA-enabled fetchmail will
automatically check for csi.com in the POP server's greeting line. If
that's found, and your user ID ends with `@compuserve.com', it will
query the server to see if it is RPA-capable, and if so do an RPA
transaction rather than a plain-text password handshake.
Warning: the debug (-v -v) output of fetchmail will show your
pass-phrase in Unicode!
These two .fetchmailrc entries show the difference between an RPA and
non-RPA configuration:
# This version will use RPA
poll csi.com via "pop.site1.csi.com" with proto POP3 and options no dns
user "CSERVE_USER@compuserve.com" there with password "CSERVE_PASSWORD"
is LOCAL_USER here options fetchall stripcr
# This version will not use RPA
poll non-rpa.csi.com via "pop.site1.csi.com" with proto POP3 and options no dns
user "CSERVE_USER" there with password "CSERVE_POP3_PASSWORD"
is LOCAL_USER here options fetchall stripcr
_________________________________________________________________
S4. How can I use fetchmail with Demon Internet's SDPS?
Single-drop mode
You can get fetchmail to download the email for just one user from
Demon Internet's POP3 server by giving it a username consisting of
your Demon user name followed by your account name, with an at-sign
between them.
For example, to download email for the user
<philh@vision25.demon.co.uk>, you could use the following .fetchmailrc
file:
set postmaster "philh"
poll pop3.demon.co.uk with protocol POP3:
user "philh@vision25" is philh
Multi-drop mode
Demon Internet's SDPS service is an implementation of POP3. All
messages have a Received: header added when they enter the maildrop,
like this:
Received: from punt-1.mail.demon.net by mailstore for fred@xyz.demon.co.uk
id 899963657:10:27896:0; Thu, 09 Jul 98 05:54:17 GMT
To enable multi-drop mode you need to tell fetchmail that 'mailstore'
is the name of the host which accepted the mail, and let it know the
hostname part(s) of your E-mail address. The following example assumes
that your hostname is xyz.demon.co.uk, and that you have also bought
"mail forwarding" for the domain my-company.co.uk (in which case your
MTA must also be configured to accept mail sent to
user@my-company.co.uk)
poll pop3.demon.co.uk proto pop3 aka mailstore no dns:
localdomains xyz.demon.co.uk my-company.co.uk
user xyz is * fetchall
The `fetchall' command ensures that all mail is downloaded. If you
want to leave mail on the server use `uidl' and `keep'; Demon does not
implement the obsolete `top' command, because SDPS combines messages
residing on two separate punt clusters into a single POP3 maildrop. If
you do use UIDL, be aware that the "user@host" form for fetching mail
from a particular Demon host will confuse fetchmail's UIDL code; use
user+host.
Note that Demon may delete mail on the server which is more than 30
days old; see their POP3 page for details.
The SDPS extension
There's a different way to do multidrop. It's not necessary on Demon
Internet, since fetchmail can parse Received addresses, but the person
who implemented this didn't know that. It may be useful if Demon
Internet ever changes mail transports.
SDPS includes a non-standard extension for retrieving the envelope of
a message (*ENV), which fetchmail optionally supports if compiled with
the --enable-SDPS option. If you have it, the first line of the
fetchmail -V response will include the string "+SDPS".
Once you have SDPS compiled in, fetchmail in POP3 mode will
automatically detect when it's talking to a Demon Internet host in
multidrop mode, and use the *ENV extension to get an envelope To
address.
The autodetection works by looking at the hostname in the POP3
greeting line; if you're accessing Demon Internet through a proxy it
may fail. To force SDPS mode, pick "sdps" as your protocol.
_________________________________________________________________
S5. How can I use fetchmail with usa.net's servers?
Enable `fetchall'. A user reports that the 2.2 version of USA.NET's
POP server reports that you must use the `fetchall' option to make
sure that all of the mail is retrieved, otherwise some may be left on
the server. This is almost certainly a server bug.
The usa.net servers (at least in their 2.2 version, June 1998) don't
handle the TOP command properly, either. Regardless of the argument
you give it, they retrieve only about 10 lines of the message.
Fetchmail normally uses TOP for message retrieval in order to avoid
marking messages seen, but `fetchall' forces it to use RETR instead.
(Note: Other failure modes have been reported on usa.net's servers.
They seem to be chronically flaky. We recommend finding another
provider.)
_________________________________________________________________
S6. How can I use fetchmail with HP OpenMail?
No special configuration is required, but OpenMail versions prior to
6.0 have an annoying bug similar to the big one in Microsoft Exchange.
The message sizes it gives in the LIST are rounded to the nearest 1024
bytes. It also has a nasty habit of discarding headers it doesn't
recognize, such as X- and Resent- headers.
As with M$ Exchange, the only real fix for these problems is to get a
POP (or preferably IMAP) server that isn't brain-dead. OpenMail's
project manager claims these bugs have been fixed in 6.0
_________________________________________________________________
S8. How can I use fetchmail with Hotmail?
You can't, yet. But Hugo Rabson has written a script called `hotmole'
that can retrieve Hotmail mail via the web using Lynx. The script is
available on Hugo Rabson's Linux page.
_________________________________________________________________
S9. How can I use fetchmail with MSN?
You can't. MSN uses something that looks like POP3, except the
authentication part is nonstandard. And of course they don't document
it, so nobody but their Windows clients can speak it.
This is a customer lock-in tactic; we recommend boycotting MSN as the
only appropriate response.
As of 5.0.8, we have support for the client side of NTLM
authentication. It's possible this may enable fetchmail to talk to
MSN; if so, somebody should report it so this FAQ can be corrected.
_________________________________________________________________
S10. How can I use fetchmail with SpryNet?
The SpryNet POP3 servers mark a message queried with TOP as seen. This
means that if your connection drops in mid-message, it may end up
invisibly stuck on your mail spool. Use the fetchall flag to ensure
that it's recovered on the next cycle.
_________________________________________________________________
K1. How can I use fetchmail with SOCKS?
Daniel Sobral <dcs@gns.com.br gave us the following recipe:
1. Install socks5. You don't need to have a socks server, you just
want the "runsocks" program.
2. Set the environment variable SOCKS_SERVER to the server you'll be
using. Alternatively, you may set SOCKS4_SERVER and/or
SOCKS5_SERVER. E.g.:
export SOCKS5_SERVER=socks.my.domain.com
3. Set SOCKS5_USER and SOCKS5_PASSWD if needed.
4. Run fetchmail through runsocks. Just like this:
runsocks fetchmail [parameters to fetchmail]
It wasn't that hard, was it? :-)
Giuseppe Guerini added a --with-socks option that supports linking
with socks library. If you specify the value of this option as
``yes'', the configure script will try to find the Rconnect library
and set the makefile up to link it. You can also specify a directory
containing the Rconnect library.
_________________________________________________________________
S7. How can I use fetchmail with geocities POP3 servers?
Nathan Cutler reports that the the mail.geocities.com POP3 servers
fail to include the first Received line of the message in the send to
fetchmail. This can solve problems if your MUA interprets Received
continuations as body lines and doesn't parse any of the following
headers.
Workaround is to use "mda" keyword or "-mda" switch:
mda "sed -e '1s/^\t/Received: /' | formail | /usr/bin/procmail -d <user>"
Replace \t with exactly one tabulation character. You should also
consider using "fetchall" option because Geocities' servers sometimes
think that the first 45 messages have already been read.
Fix: Get an email provider that doesn't suck. Geocities' pop-up adds
are lame, you should boycott them anyway.
_________________________________________________________________
K2. How can I use fetchmail with IPv6 and IPsec?
To use fetchmail with IPv6, you need a system that supports IPv6, the
"Basic Socket Interface Extensions for IPv6" (RFC 2133), and the
inet6-apps kit. This currently means that you need to have a BSD/OS or
NetBSD system with the NRL IPv6+IPsec software distribution or a Linux
system with the latest experimental kernel and net-tools. It should
not be hard to build fetchmail on other IPv6 implementations if you
can port the inet6-apps kit.
To use fetchmail with networking security (read: IPsec), you need a
system that supports IPsec, the API described in the "Network Security
API for Sockets" (draft-metz-net-security-api-01.txt), and the
inet6-apps kit. This currently means that you need to have a BSD/OS or
NetBSD system with the NRL IPv6+IPsec software distribution. A Linux
IPsec implementation supporting this API will probably appear in the
coming months.
The NRL IPv6+IPsec software distribution can be obtained from:
http://web.mit.edu/network/isakmp
The inet6-apps kit can be obtained from
ftp://ftp.ipv6.inner.net/pub/ipv6 (via IPv6) or
ftp://ftp.inner.net/pub/ipv6 (via IPv4).
More information on using IPv6 with Linux can be obtained from:
* http://www.bieringer.de/linux/IPv6/IPv6-HOWTO/IPv6-HOWTO.html
* http://www.ipv6.inner.net/ipv6 (via IPv6)
* http://www.inner.net/ipv6 (via IPv4)
_________________________________________________________________
K3. How can I get fetchmail to work with ssh?
We have three recipes for this. The first is easy to set up, but only
supports one user at a time.
First, a lightly edited version of a recipe from Masafumi NAKANE:
1. You must have ssh (the ssh client) on the local host and sshd (ssh
server) on the remote mail server. And you have to configure ssh so
you can login to the sshd server host without a password. (Refer to
ssh man page for several authentication methods.)
2. Add something like following to your .fetchmailrc file:
poll mailhost port 1234 via localhost with proto pop3:
preconnect "ssh -f -L 1234:mailhost:110 mailhost sleep 20 </dev/null >/
dev/null";
(Note that 1234 can be an arbitrary port number. Privileged ports can
be specified only by root.) The effect of this ssh command is to
forward connections made to localhost port 1234 (in above example) to
mailhost's 110.
This configuration will enable secure mail transfer. All the
conversation between fetchmail and remote pop server will be
encrypted.
If sshd is not running on the remote mail server, you can specify
intermediate host running it. If you do this, however, communication
between the machine running sshd and the POP server will not be
encrypted. And the preconnect line would be like this:
preconnect "ssh -f -L 1234:mailhost:110 sshdhost sleep 20 </dev/null >/dev/null
"
You can work this trick with IMAP too, but the port number 110 in the
above would need to become 143.
Second, a recipe from Charlie Brady <cbrady@ind.tansu.com.au>:
Charlie says: "The [previous] recipe certainly works, but the solution
I post here is better in a few respects":
* this method will not fail if two or more users attempt to use
fetchmail simultaneously.
* you are able to use the full facilities of tcpd to control access
* this method does not depend on the preconnect feature of
fetchmail, so can be used for tunneling of other services as well.
Here are the steps:
1. Make sure that the "socket" program is installed on the server
machine. Presently it lives at
ftp://sunsite.unc.edu/pub/linux/system/network/misc/socket-1.1.ta
r.gz, but watch out for a change in version number.
2. Set up an unprivileged account on your system with a .ssh
directory containing an SSH identity file "identity" with no pass
phrase, "identity.pub" and "known_hosts" containing the host key
of your mailhost. Let's call this account "noddy".
3. On mailhost, set up no-password access for noddy@yourhost. Add to
your SSH authorized_keys file:
command="socket localhost 110",no-port-forwarding 1024 ......
where "1024 ......" is the content of noddy's identity.pub file.
4. Create a script /usr/local/bin/ssh.fm and make it executable:
#! /bin/sh
exec ssh -q -C -l your.login.id -e none mailhost socket localhost 110
5. Add an entry in inetd.conf for whatever port you choose to use -
say:
1234 stream tcp nowait noddy /usr/sbin/tcpd /usr/local/bin/ssh.fm
6. Send a HUP signal to your inetd.
Now just use localhost:1234 to access your POP server.
For yet a third recipe, see Secure POP via SSH mini-HOWTO.
_________________________________________________________________
K4. What do I have to do to use the IMAP-GSS protocol?
Fetchmail can use RFC1731 GSSAPI authorization to safely identify you
to your IMAP server, as long as you can share Kerberos V credentials
with your mail host and you have a GSSAPI-capable IMAP server. UW-IMAP
(available via FTP at ftp.cac.washington.edu) is the only one I'm
aware of and the one I recommend anyway for other reasons. You'll need
version 4.1-FINAL or greater though, and it has to have GSS support
compiled in.
Neither UW-IMAP nor fetchmail compile in support for GSS by default,
since it requires libraries from the Kerberos V distribution
(available via FTP at athena-dist.mit.edu but mind the export
restrictions). If you have these, compiling in GSS support is simple:
add a
--with-gssapi=[/path/to/krb5/root]
option to configure. For instance, I have all of my Kerberos V
libraries installed under /usr/krb5 so I run
configure --with-gssapi=/usr/krb5
Setting up Kerberos V authentication is beyond the scope of this FAQ
(you may find Jim Rome's paper How to Kerberize your site helpful),
but you'll at least need to add a credential for imap/[mailhost] to
the keytab of the mail server (IMAP doesn't just use the host key).
Then you'll need to have your credentials ready on your machine (cf.
kinit).
After that things are very simple. Set your protocol to imap-gss in
your .fetchmailrc, and omit the password, since imap-gss doesn't need
one. You can specify a username if you want, but this is only useful
if your mailbox belongs to a username different from your Kerberos
principal.
Now you don't have to worry about your password appearing in cleartext
in your .fetchmailrc, or across the network.
_________________________________________________________________
K5. How can I use fetchmail with SSL?
The U.S. government's never-to-be-sufficiently-damned EAR regulations
prevent me from including SSL library hooks in the distribution.
However, the First Amendment of the U.S. Constitution hasn't been
eviscerated (not yet, anyway -- our would-be totalitarians are working
on trashing the Second Amendment first).
Option 1:
I can therefore safely tell you, in documentation, that there appears
to be a way to set up an SSL command chain using the `plugin' option
(originally designed for handling proxy connections across firewalls).
Get your hands on the SSLeay code. Now make yourself a script called
`ssl_connect' that calls the SSLeay utility `s_client' as follows:
/usr/local/ssl/bin/s_client -quiet -ssl2 -connect $1:$2
Now add `plugin ssl_connect' to the server options for your
connection.
Option 2:
For those in the U.S., there is a set of SSL patches for fetchmail
available from the North American Cryptographic Archives, in the SSL
directory. You have to answer three questions about your qualification
to access the archive, before you are allowed in. You can enter
through the main page for the server and browse the archive, or you
can go straight to the SSL directory. There you will find patch files
against the fetchmail release sources as well as patched source
tarballs.
While we cannot make the SSL sources available to anyone outside of
the U.S. at this time, if the patches do leak out of the U.S. through
no fault of our own, and someone informs us of their location, we can
provide the URL pointing to archive sites outside of the U.S.
Newer versions of the SSL patches make appear in the `new' directory
and stay there a while until they can be processed and moved to the
SSL directory. Check for patches in `new' if you do not find patches
for the latest fetchmail release.
_________________________________________________________________
R1. Fetchmail isn't working, and -v shows `SMTP connect failed' messages.
Fetchmail itself is probably working, but your SMTP port 25 listener
is down or inaccessible.
The first thing to check is if you can telnet to port 25 on your smtp
host (which is normally `localhost' unless you've specified an smtp
option in your .fetchmailrc or on the command line) and get a greeting
line from the listener. If the SMTP host is inaccessible or the
listener is down, fix that first.
If the listener seems to be up when you test with telnet, the most
benign and typical problem is that the listener had a momentary
seizure due to resource exhaustion while fetchmail was polling it --
process table full or some other problem that stopped the listener
process from forking. If your SMTP host is not `localhost' or
something else in /etc/hosts, the fetchmail glitch could also have
been caused by transient nameserver failure.
Try running fetchmail -v again; if it succeeds, you had one of these
kinds of transient glitch. You can ignore these hiccups, because a
future fetchmail run will get the mail through.
If the listener tests up, but you have chronic failures trying to
connect to it anyway, your problem is more serious. One way to work
around chronic SMTP connect problems is to use --mda. But this only
attacks the symptom; you may have a DNS or TCP routing problem. You
should really try to figure out what's going on underneath before it
bites you some other way.
We have one report (from toby@eskimo.com) that you can sometimes solve
such problems by doing an smtp declaration with an IP address that
your routing table maps to something other than the loopback device
(he used ppp0).
We also have a report that this error can be caused by having an
/etc/hosts file that associates your client host name with more than
one IP address.
It's also possible that your DNS configuration isn't looking at
/etc/hosts at all. If you're using libc5, look at /etc/resolv.conf; it
should say something like
order hosts,bind
so your /etc/hosts file is checked first. If you're running GNU libc6,
check your /etc/nsswitch.conf file. Make sure it says something like
hosts: files dns
again, in order to make sure /etc/hosts is seen first.
If you have a hostname set for your machine, and this hostname does
not appear in /etc/hosts, you will be able to telnet to port 25 and
even send a mail with rcpt to: user@host-not-in-/etc/hosts, but
fetchmail can't seem to get in touch with sendmail, no matter what you
set smtpaddress to.
We had another report from a Linux user of fetchmail 2.1 who solved
his SMTP connection problem by removing the reference to -lresolv from
his link line and relinking. Apparently in some older Linux
distributions the libc bind library version works better.
As of 2.2, the configure script has been hacked so the bind library is
linked only if it is actually needed. So under Linux it won't be, and
this particular cause should go away.
_________________________________________________________________
R2. When I try to configure an MDA, fetchmail doesn't work.
(I hear this one from people who have run into the blank-line problem
in X1.)
Try sending yourself test mail and retrieving it using the
command-line options `-k -m cat'. This will dump exactly what
fetchmail retrieves to standard output (plus the Received line
fetchmail itself adds to the headers).
If the dump doesn't match what shows up in your mailbox when you
configure an MDA, your MDA is mangling the message. If it doesn't
match what you sent, then fetchmail or something on the server is
broken.
_________________________________________________________________
R3. Fetchmail dumps core when given an invalid rc file.
This is usually reported from AIX or Ultrix, but has even been known
to happen on Linuxes without a recent version of flex installed. The
problem appears to be a result of building with an archaic version of
lex.
Workaround: fix the syntax of your .fetchmailrc file.
Fix: build and install the latest version of flex from the Free
Software Foundation. An FSF mirror site will help you get it faster.
_________________________________________________________________
R4. Fetchmail dumps core in -V mode, but operates normally otherwise.
We've had this reported to us under Linux using libc-5.4.17 and
gcc-2.7.2. It does not occur with libc-5.3.12 or earlier versions.
Workaround: link with GNU malloc rather than the stock C library
malloc.
We're told there is some problem with the malloc() code in that
version which makes it fragile in the presence of multiple free()
calls on the same pointer (the malloc arena gets corrupted).
Unfortunately it appears from doing gdb traces that whatever free()
calls producing the problem are being made by the C library itself,
not the fetchmail code (they're all from within fclose, and not an
fclose called directly by fetchmail, either).
_________________________________________________________________
R5. Running fetchmail in daemon mode doesn't work.
We have one report from a SunOS 4.1.4 user that trying to run
fetchmail in detached daemon mode doesn't work, but that using the
same options with -N (nodetach) is OK.
If this happens, you have a specific portability problem with the code
in daemon.c that detaches and backgrounds the daemon fetchmail. Tell
me about it so I can try to fix it. As a workaround, you can start
fetchmail with -N and an ampersand to background it.
This should not happen under Linux or any truly POSIX-conformant Unix.
_________________________________________________________________
R6. Fetchmail hangs when used with pppd.
Your problem may be with pppd's `demand' option. We have a report that
fetchmail doesn't play well with it, but works with pppd if `demand'
is turned off. We have no idea why this is.
_________________________________________________________________
R7. Fetchmail randomly dies with socket errors.
Check the MTU value in your PPP interface reported by /sbin/ifconfig.
If it's over 600, change it in your PPP options file.
(/etc/ppp/options on my box). Here are option values that work:
mtu 552
mru 552
_________________________________________________________________
R8. Fetchmail running as root stopped working after an OS upgrade In
RH 6.0, the HOME value in the boot-time root environment changed from
/root to / as the result of a change in init. Move your .fetchmailrc
or use a -f option to explicitly point at the file. (Oddly, a similar
problem has been reported from Debian systems.)
_________________________________________________________________
R9. Fetchmail is timing out after fetching certain messages but before deleting
them
There's a TCP/IP stalling problem under Redhat 6.0 (and possibly other
recent Linuxes) that can cause this symptom. Brian Boutel writes:
TCP timestamps are turned on on my Linux boxes (I assume it's now
the default). This uses 12 extra bytes per segment. When the tcp
connection starts, the other end agrees a MSS of 1460, and then
fragments 1460 byte chunks into 1448 and 12, because is is not
allowing for the timestamp.
Then, for reasons I can't explain, it waits a long time (typically
2 minutes) after the ack is sent before sending the next
(fragmented) packet. Turning off tcp timestamps avoids the
fragmentation and restores normal behaviour. To do this, [execute]
echo 0 > /proc/sys/net/ipv4/tcp_timestamps
I'm still unclear about the details of why this is happening. At
least [now] I am now getting good performance and no queue
blocking.
_________________________________________________________________
D1. I think I've set up fetchmail correctly, but I'm not getting any mail.
Maybe you have a .forward or alias set up that you've forgotten about.
You should probably remove it.
Or maybe you're trying to run fetchmail in multidrop mode as root
without a .fetchmailrc file. This doesn't do what you think it should;
see question C1.
Or you may not be connecting to the SMTP listener. Run fetchmail -v
and see R1.
_________________________________________________________________
D2. All my mail seems to disappear after a dropped connection.
One POP3 daemon used in the Berkeley Unix world that reports itself as
POP3 version 1.004 actually throws the queue away. 1.005 fixed that.
If you're running this one, upgrade immediately. (It also truncates
long lines at column 1024)
Many POP servers, if an interruption occurs, will restore the whole
mail queue after about 10 minutes. Others will restore it right away.
If you have an interruption and don't see it right away, cross your
fingers and wait ten minutes before retrying.
Some servers (such as Microsoft's NTMail) are mis-designed to restore
the entire queue, including messages you have deleted. If you have one
of these and it flakes out on you a lot, try setting a small
--fetchlimit value. This will result in more IP connects to the
server, but will mean it actually executes changes to the queue more
often.
Qualcomm's qpopper, used at many BSD Unix sites, is better behaved. If
its connection is dropped, it will first execute all DELE commands as
though you had issued a QUIT (this is a technical violation of the
POP3 RFCs, but a good idea in a world of flaky phone lines). Then it
will re-queue any message that was being downloaded at hangup time.
Still, qpopper may require a noticeable amount of time to do deletions
and clean up its queue. (Fetchmail waits a bit before retrying in
order to avoid a `lock busy' error.)
_________________________________________________________________
D3. Mail that was being fetched when I interrupted my fetchmail seems to have
been vanished.
Fetchmail only sends a delete mail request to the server when either
(a) it gets a positive delivery acknowledgment from the SMTP listener,
or (b) it gets an error 571 (the spam-filter error) from the listener.
No interrupt can cause it to lose mail.
However, IMAP2bis has a design problem in that its normal fetch
command marks a message `seen' as soon as the fetch command to get it
is sent down. If for some reason the message isn't actually delivered
(you take a line hit during the download, or your port 25 listener
can't find enough free disk space, or you interrupt the delivery in
mid-message) that `seen' message can lurk invisibly in your server
mailbox forever.
Workaround: add the `fetchall' keyword to your fetch options.
Solution: switch to an IMAP4 server.
_________________________________________________________________
M1. I've declared local names, but all my multidrop mail is going to root
anyway.
Somehow your fetchmail is never recognizing the hostname part of
recipient names it parses out of To/Cc/envelope-header lines as
matching the name of the mailserver machine. To check this, run
fetchmail in foreground with -v -v on. You will probably see a lot of
messages with the format ``line rejected, %s is not an alias of the
mailserver'' or ``no address matches; forwarding to %s.''
These errors usually indicate some kind of DNS configuration problem
either on the server or your client machine.
The easiest workaround is to add a `via' option (if necessary) and add
enough aka declarations to cover all of your mailserver's aliases,
then say `no dns'. This will take DNS out of the picture (though it
means mail may be uncollected if it's sent to an alias of the
mailserver that you don't have listed).
It would be better to fix your DNS, however. DNS problems can hurt you
in lots of ways, for example by making your machines intermittently or
permanently unreachable to the rest of the net.
Occasionally these errors indicate the sort of header-parsing problem
described in M7.
_________________________________________________________________
M2. I can't seem to get fetchmail to route to a local domain properly.
A lot of people want to use fetchmail as a poor man's internetwork
mail gateway, picking up mail accumulated for a whole domain in a
single server mailbox and then routing based on what's in the
To/Cc/Bcc lines.
In general, this is not really a good idea. It would be smarter to
just let the mail sit in the mailserver's queue and use fetchmail's
ETRN mode to trigger SMTP sends periodically (of course, this means
you have to poll more frequently than the mailserver's expiration
period). If you can't arrange this, try setting up a UUCP feed.
If neither of these alternatives is available, multidrop mode may do
(though you are going to get hurt by some mailing list software; see
the caveats under THE USE AND ABUSE OF MULTIDROP MAILBOXES on the man
page). If you want to try it, the way to do it is with the
`localdomains' option.
In general, if you use localdomains you need to make sure of two other
things:
1. You've actually set up your .fetchmailrc entry to invoke multidrop
mode.
Many people set a `localdomains' list and then forget that fetchmail
wants to see more than one name (or the wildcard `*') in a `here' list
before it will do multidrop routing.
2. You may have to set `no envelope'.
Normally, multidrop mode tries to deduce an envelope address from a
message before parsing the To/Cc/Bcc lines (this enables it to avoid
losing to mailing list software that doesn't put a recipient address
in the To lines).
Some ways of accumulating a whole domain's messages in a single server
mailbox mean it all ends up with a single envelope address that is
useless for rerouting purposes. You may have to set `no envelope' to
prevent fetchmail from being bamboozled by this.
Check also answer T1 on a reliable way to do multidrop delivery if
your ISP (or your mail redirection provider) is using qmail.
_________________________________________________________________
M3. I tried to run a mailing list using multidrop, and I have a mail loop!
This isn't fetchmail's fault. Check your mailing list. If the list
expansion includes yourself or anybody else at your mailserver (that
is, not on the client side) you've created a mail loop. Just chop the
host part off any local addresses in the list.
If you use sendmail, you can check the list expansion with sendmail
-bv.
_________________________________________________________________
M4. My multidrop fetchmail seems to be having DNS problems.
We have one report from a Linux user (not the same one as in R1!) who
solved this problem by removing the reference to -lresolv from his
link line and relinking. Apparently in some older Linux distributions
the libc5 bind library version works better.
As of 2.2, the configure script has been hacked so the bind library is
linked only if it is actually needed. So under Linux it won't be, and
this problem should go away.
_________________________________________________________________
M5. I'm seeing long DNS delays before each message is processed.
Use the `aka' option to pre-declare as many of your mailserver's DNS
names as you can. When an address's host part matches an aka name, no
DNS lookup needs to be done to check it.
If you're sure you've pre-declared all of your mailserver's DNS names,
you can use the `no dns' option to prevent other hostname parts from
being looked up at all.
Sometimes delays are unavoidable. Some SMTP listeners try to call DNS
on the From-address hostname as a way of checking that the address is
valid.
_________________________________________________________________
M6. How do I get multidrop mode to work with majordomo?
In order for sendmail to execute the command strings in the majordomo
alias file, it is necessary for sendmail to think that the mail it
receives via SMTP really is destined for a local user name. A normal
virtual-domain setup results in delivery to the default mailbox,
rather than expansion through majordomo.
Michael <michael@bizsystems.com> gave us a recipe for dealing with
this case that pairs a run control file like this:
poll your.pop3.server proto pop3:
no envelope no dns
localdomains virtual.localdomain1.com virtual.localdomain2.com ...
user yourISPusername is root * here,
password yourISPpassword fetchall
with a hack on your local sendmail.cf like this:
#############################################
# virtual info, local hack for ruleset 98 #
#############################################
# domains to treat as direct mapped local domain
CVvirtual.localdomain1.com virtual.localdomain2.com ...
---------------------------
in ruleset 98 add
-------------------------
# handle virtual users
R$+ <@ $=V . > $: $1 < @ $j . >
R< @ > $+ < @ $=V . > $: $1 < @ $j . >
R< @ > $+ $: $1
R< error : $- $+ > $* $#error $@ $1 $: $2
R< $+ > $+ < @ $+ > $: $>97 $1
This ruleset just strips virtual domain names off the addresses of
incoming mail. Your sendmail must be 8.8 or newer for this to work.
Michael says:
I use this scheme with 2 virtual domains and the default ISP
user+domain and service about 30 mail accounts + majordomo on my
inside pop3 server with fetchmail and sendmail 8.83
_________________________________________________________________
M7. Multidrop mode isn't parsing envelope addresses from my Received headers as
it should.
It may happen that you're getting what appear to be well-formed
sendmail Received headers, but fetchmail can't seem to extract an
envelope address from them. There can be a couple of reasons for this.
Spurious Received lines need to be skipped:
First, fetchmail might be looking at the wrong Received header.
Normally it looks only on the first one it sees, on the theory that
that one was last added and is going to be the one containing your
mailserver's theory of who the message was addressed to.
Some (unusual) mailserver configurations will generate extra Received
lines which you need to skip. To arrange this, use the optional skip
prefix argument of the `envelope' option; you may need to say
something like `envelope 1 Received' or `envelope 2 Received'.
The `by' clause doesn't contain a mailserver alias:
When fetchmail parses a Received line that looks like
Received: from send103.yahoomail.com (send103.yahoomail.com [205.180.60.92])
by iserv.ttns.net (8.8.5/8.8.5) with SMTP id RAA10088
for <ksturgeon@fbceg.org>; Wed, 9 Sep 1998 17:01:59 -0700
it checks to see if `iserv.ttns.net' is a DNS alias of your mailserver
before accepting `ksturgeon@fbceg.org' as an envelope address. This
check might fail if your DNS were misconfigured, or if you were using
`no dns' and had failed to declare iserv.ttns.net as an alias of your
server.
_________________________________________________________________
X1. Spurious blank lines are appearing in the headers of fetched mail.
What's probably happening is that the POP/IMAP daemon on your
mailserver is inserting a non-RFC822 header (like X-POP3-Rcpt:) and
something in your delivery path (most likely an old version of the
deliver program, which sendmail often calls to do local delivery) is
failing to recognize it as a header.
This is not fetchmail's problem. The first thing to try is installing
a current version of deliver. If this doesn't work, try to figure out
which other program in your mail path is inserting the blank line and
replace that. If you can't do either of these things, pick a different
MDA (such as procmail) and declare it with the `mda' option.
_________________________________________________________________
X2. My mail client can't see a Subject line.
First, see X1. This is quite probably the same problem (X-POP3-Rcpt
header or something similar being inserted by the server and choked on
by an old version of deliver).
The O'Reilly sendmail book does warn that IDA sendmail doesn't process
X- headers correctly. If this is your problem, all I can suggest is
replacing IDA sendmail, because it's broken and not RFC822 conformant.
_________________________________________________________________
X3. Messages containing "From" at start of line are being split.
If you know the messages aren't split in your server mailbox, then
this is a problem with your POP/IMAP server, your client-side SMTP
listener or your local delivery agent. Fetchmail cannot split
messages.
Some POP server daemons ignore Content-Length headers and split
messages on From lines. We have one report that the 2.1 version of the
BSD popper program (as distributed on Solaris 2.5 and elsewhere) is
broken this way.
You can test this. Declare an mda of `cat' and send yourself one piece
of mail containing "From" at start of a line. If you see a split
message, your POP/IMAP server is at fault. Upgrade to a more recent
version.
Sendmail and other SMTP listeners don't split RFC822 messages either.
What's probably happening is either sendmail's local delivery agent or
your mail reader are not quite RFC822-conformant and are breaking
messages on what it thinks are Unix-style From headers. You can figure
out which by looking at your client-side mailbox with vi or more. If
the message is already split in your mailbox, your local delivery
agent is the problem. If it's not, your mailreader is the problem.
If you can't replace the offending program, take a look at your
sendmail.cf file. There will likely be a line something like
Mlocal, P=/usr/bin/procmail, F=lsDFMShP, S=10, R=20/40, A=procmail -Y -d $u
describing your local delivery agent. Try inserting the `E' option in
the flags part (the F= string). This will make sendmail turn each
dangerous start-of-line From into a >From, preventing programs further
downstream from acting up.
_________________________________________________________________
X4. My mail is being mangled in a new and different way
The first thing you need to do is pin down what program is doing the
mangling. We don't like getting bug reports about fetchmail that are
actually due to some other program's malfeasance, so please go through
this diagnostic sequence before sending us a complaint.
There are five possible culprits to consider, listed here in the order
they pass your mail:
1. Programs upstream of your server mailbox.
2. The POP or IMAP server on your mailserver host.
3. The fetchmail program itself.
4. Your local sendmail.
5. Your LDA (local delivery agent), as called by sendmail or
specified by mda.
Often it happens that fetchmail itself is OK, but using it exposes
pre-existing bugs in your downstream software, or your downstream
software has a bad interaction with POP/IMAP. You need to pin down
exactly where the message is being garbled in order to deduce what is
actually going on.
The first thing to do is send yourself a test message, and retrieve it
with a .fetchmailrc entry containing the following (or by running with
the equivalent command-line options):
mda "cat >MBOX" keep fetchall
This will capture what fetchmail gets from the server, except for (a)
the extra Received header line fetchmail prepends, (b) header address
changes due to rewrite, and (c) any end-of-line changes due to the
forcecr and stripcr options. MBOX will in fact contain what programs
downstream of fetchmail see.
The most common causes of mangling are bugs and misconfigurations in
those downstream programs. If MBOX looks unmangled, you will know that
is what is going on and that it is not fetchmail's problem. Take a
look at the other FAQ items in this section for possible clues about
how to fix your problem.
If MBOX looks mangled, the next thing to do is compare it with your
actual server mailbox (if possible). That's why you specified keep, so
the server copy would not be deleted. If your server mailbox looks
mangled, programs upstream of your server mailbox are at fault.
Unfortunately there is probably little you can do about this aside
from complaining to your site postmaster, and nothing at all fetchmail
can do about it!
More likely you'll find that the server copy looks OK. In that case
either the POP/IMAP server or fetchmail is doing the mangling. To
determine which, you'll need to telnet to the server port and simulate
a fetchmail session yourself. This is not actually hard (both POP3 and
IMAP are simple, text-only, line-oriented protocols) but requires some
attention to detail. You should be able to use a fetchmail -v log as a
model for a session, but remember that the "*" in your LOGIN or PASS
command dump has to be replaced with your actual password.
The objective of manually simulating fetchmail is so you can see
exactly what fetchmail sees. If you see a mangled message, then your
server is at fault, and you probably need to complain to your
mailserver administrators. However, we like to know what the broken
servers are so we can warn people away from them. So please send us a
transcript of the session including the mangling and the server's
initial greeting line. Please tell us anything else you think might be
useful about the server, like the server host's operating system.
If your manual fetchmail simulation shows an unmangled message,
congratulations. You've found an actual fetchmail bug, which is a
pretty rare thing these days. Complain to us and we'll fix it. Please
include the session transcript of your manual fetchmail simulation
along with the other things described in the FAQ entry on reporting
bugs.
_________________________________________________________________
X5. Using POP3, retrievals seems to be fetching too much!
This may happen in versions of fetchmail after 4.4.1 and before 4.4.8.
Versions after 4.4.1 use POP3's TOP command rather than RETR, in order
to avoid marking the message seen (leaving it unseen is helpful for
later recovery if you lose your connection in the middle of a
retrieval).
Versions of fetchmail from 4.4.2 through 4.4.7 had a bad interaction
with Eudora qpopper versions 2.3 and later. The TOP bounds check was
fooled by an overflow condition in the TOP argument. Decrementing the
TOP argument in 4.4.7 fixed this.
Fix: Upgrade to a later version of fetchmail.
Workaround: set the fetchall option. Under POP3 in these fetchmail
version only, this had the side effect of forcing RETR use.
_________________________________________________________________
O1. The --logfile option doesn't work if the logfile doesn't exist.
This is a feature, not a bug. It's in line with normal practice for
system daemons and allows you to suppress logging by removing the log,
without hacking potentially fragile startup scripts. To get around it,
just touch(1) the logfile before you run fetchmail (this will have no
effect on the contents of the logfile if it already exists).
_________________________________________________________________
O2. Every time I get a POP or IMAP message the header is dumped to all my
terminal sessions.
Fetchmail uses the local sendmail to perform final delivery, which
Netscape and other clients doesn't do; the announcement of new
messages is done by a daemon that sendmail pokes. There should be a
``biff'' command to control this. Type
biff n
to turn it off. If this doesn't work, try the command
chmod -x `tty`
which is essentially what biff -n will do. If this doesn't work,
comment out any reference to ``comsat'' in your /etc/inetd.conf file
and restart inetd.
In Slackware Linux distributions, the last line in /etc/profile is
biff y
Change this to
biff n
to solve the problem system-wide.
_________________________________________________________________
O3. Does fetchmail reread its rc file every poll cycle?
No. Fetchmail only reads the rc file once, when it starts up. To force
an rc file reread, do fetchmail -q; fetchmail.
_________________________________________________________________
O4. Why do deleted messages show up again when I take a line hit while
downloading?
Because you're using a POP3 other than Qualcomm qpopper, or an IMAP
with a long expunge interval.
According to the POP3 RFCs, deletes aren't actually performed until
you issue the end-of-session QUIT command. Fetchmail cannot fix this,
because doing it right takes cooperation from the server. There are
two possible remedies:
One is to switch to qpopper (the free POP3 server from Qualcomm, the
Eudora people). The qpopper software violates the POP3 RFCs by doing
an expunge (removing deleted messages) on a line hangup, as well as on
processing a QUIT command.
The other (which we recommend) is to switch to IMAP. IMAP has an
explicit expunge command and fetchmail normally uses it to delete
messages immediately after they are downloaded.
If you get very unlucky, you might take a line hit in the window
between the delete and the expunge. If you've set a longer expunge
interval, the window gets wider. This problem should correct itself
the next time you complete a successful query.
_________________________________________________________________
O5. Why is fetched mail being logged with my name, not the real From address?
Because logging is done based on the address indicated by the sending
SMTP's MAIL FROM, and some listeners are picky about that address.
Some SMTP listeners get upset if you try to hand them a MAIL FROM
address naming a different host than the originating site for your
connection. This is a feature, not a bug -- it's supposed to help
prevent people from forging mail with a bogus origin site. (RFC 1123
says you shouldn't do this exclusion...)
Since the originating site of a fetchmail delivery connection is
localhost, this effectively means these picky listeners will barf on
any MAIL FROM address fetchmail hands them with an @ in it!
Versions 2.1 and up try the header From address first and fall back to
the calling-user ID. So if your SMTP listener isn't picky, the log
will look right.
_________________________________________________________________
O6. I'm seeing long sendmail delays or hangs near the start of each poll cycle.
Sendmail does a hostname lookup when it first starts up, and also each
time it gets a HELO in listener mode.
Your resolver configuration may be causing one of these lookups to
fail and time out. Check /etc/resolv.conf and /etc/hosts file. Make
sure your hostname and fully-qualified domain name are both in
/etc/hosts, and that hosts is looked at before DNS is queried. You
probably also want your remote mail server(s) to be in the hosts file.
You can suppress the startup-time lookup if need to by reconfiguring
with FEATURE(nodns).
Configuring your bind library to cache DNS lookups locally may help,
and is a good idea for speeding up other services as well. Switching
to a faster MTA like qmail or exim might help.
_________________________________________________________________
O7. Why doesn't fetchmail deliver mail in date-sorted order?
Because that's not the order the server hands it to fetchmail in.
Fetchmail getting mail from a POP server delivers mail in the order
that your server delivers mail. Fetchmail can't do anything about
this; it's a limitation of the underlying POP protocol.
In theory it might be possible for fetchmail in IMAP mode to sort
messages by date, but this would be in violation of two basics of
fetchmail's design philosophy: (a) to be as simple and transparent a
pipe as possible, and (b) to hide, rather than emphasize, the
differences between the remote-fetch protocols it uses.
Re-ordering messages is a user-agent function, anyway.
_________________________________________________________________
O8. I'm using pppd. Why isn't my monitor option working?
There is a combination of circumstances that can confuse fetchmail. If
you have set up demand dialing with pppd, and pppd has an idle
timeout, and you have lcp-echo-interval set, then the
lcp-echo-interval time must be longer than the pppd idle timeout.
Otherwise it is going keep increasing the packet counters that
fetchmail relies upon, triggering fetchmail into polling after its own
delay interval and thus preventing the pppd link from ever reaching
its inactivity timeout.
_________________________________________________________________
Back to Fetchmail Home Page To Site Map $Date: 1999/09/23 17:21:40 $
Eric S. Raymond <esr@snark.thyrsus.com>