The Fetchmail FAQ
Description: Frequently asked questions about fetchmail.
Keywords: fetchmail, POP, POP2, POP3, IMAP, remote mail

Back to Fetchmail Home Page | To Site Map | $Date: 1997/08/11 20:03:53 $

# 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?

# 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?

# 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 get fetchmail to work with ssh?
C5. How can I set up support for sendmail's anti-spam 571 response?
C6. How can I do automatic startup/shutdown of fetchmail when I may have multiple login sessions going?

# Configuration tips for non-sendmail MTAs

T1. How can I use fetchmail with qmail?
T2. How can I use fetchmail with exim?
T3. How can I use fetchmail with smail?
T4. How can I use fetchmail with Lotus Notes?

# Runtime fatal errors:

R1. I think I've set up fetchmail correctly, but I'm not getting any mail.
R2. Fetchmail isn't working, and -v shows `SMTP connect failed' messages.
R3. When I try to configure an MDA, fetchmail doesn't work.
R4. Fetchmail dumps core in -V mode, but operates normally otherwise.
R5. Mail that was being fetched when I interrupted my fetchmail seems to have been vanished. R6. Fetchmail dumps core when I use a .netrc file but works otherwise.
R7. All my mail seems to disappear after an interrupt.

# 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?

# Mangled mail:

X1. Why is fetched mail being logged with my name, not the real From address?
X2. Spurious blank lines are appearing in the headers of fetched mail.
X3. My mail client can't see a Subject line.
X4. Messages containing "From" at start of line are being split.

# 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.

# 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. Extensive testing by a large, multi-platform user community has shown that it is as near bulletproof as the underlying protocols permit.

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.ccil.org/~esr/fetchmail. You can also 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. When reporting bugs, please include the following:

1. Your operating system and compiler version.
2. Any command-line options you used.
3. The output of fetchmail -V called with whatever other command-line options you used.

It is helpful if you include your .fetchmailrc, but not necessary unless your symptom seems to involve an error in configuration parsing.

A transcript of the failed session with -v on is almost always useful. 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 br 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 mailagent 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.

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.

The list is at fetchmail-friends@thyrsus.com and is a SmartList reflector; sign up in the usual way with a message containing the word "subscribe" in the subject line sent to to fetchmail-friends-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?

Now it can be told! 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.

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.

## F1. Why does my old .fetchmailrc file no longer work?

### 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:

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.

So put string quotes around it. :-)

The configuration file parser treats any all-numeric token as a number, which will confuse it when it's expecting a name. String quoting forces the token's class.

## F3. The .fetchmailrc parser won't accept my host or username beginning with `no'.

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.).

You can work around this easily. Just put string quotes around your token.

I haven't fixed this because there is no good fix for it short of implementing a token pushback stack in the lexer. That's more additional complexity than I'm willing to add to banish a very marginal bug with an easy workaround.

## 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)

in order to migrate. 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 anymore 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 two 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.

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.

## 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' (ie. 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?

Fetchmail versions before 2.3 actually used SIGHUP as a wakeup signal. Newer versions use SIGUSR1 for wakeup (and SIGHUP only in background-daemon mode) in order to avoid any potential confusion about logout-time behavior. The right way to dispatch fetchmail on logout 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.

## 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 ', where 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 get fetchmail to work with ssh?

We have two recipes for this. The first is a little easier 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 pop3:
            preconnect "ssh -f -L 1234:mailhost:110 mailhost sleep 20 /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"

You can work this trick with IMAP too, but the port number 110 in the above would need to become 143.

Second, a recipe frm 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.
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 authorised_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.

## C5. How can I set up support for sendmail's anti-spam 571 response?

Rachel Polanskis writes:

Basically you need to use the "check_*" rules in sendmail. These are rules introduced since version 8.8.2

The idea is to generate a list of domains and addresses that are placed into a file - I call mine "sendmail.rej" and you place just one domain or email address on each line. During the SMTP transaction, this file is checked and if there is a match, the message is refused, with a suitable "Service not available" message sent back to the sender.

With the feature enabled in fetchmail, the mail is simply deleted, with no further processing.

The only drawback when blocking spam with fetchmail is that you do not get the satisfaction of sending an error back to the sender.

To actually use the check_mail rules in sendmail 8.8.2 or better, you need to know how to generate a sendmail.cf file from the m4 config files distributed with sendmail.

The actual rules can be found at the following URLS:

http://www.informatik.uni-kiel.de/%7Eca/email/check.html

This one is by Claus Aßman, who has documented more of sendmail then I can digest! The actual setup I used though was by David Begley, who has put together a WWW page describing how to quickly implement these rules yourself.

http://www.nepean.uws.edu.au/users/david/pe/blockmail.html

David's pages could be moving shortly. I will post an update if it happens.

Remember, when copying these rulesets off the web, that there are tabs embedded in them, that may not be preserved. You must reintroduce these tabs into the rules to make them work properly.

Once you have your ruleset in place, and have generated a nice sendmail.cf file, and the list of blocked sites, try telneting to your SMTP port to test it, and send a message with a blocked address in it.

You should see a message similar to:

         "571 unsolicited email is refused"

Next, if you have access to a host that you can send mail from, that is not your mail host, add that host to your spamlist and restart sendmail.

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!!!

The check_ rules work, and they work well. Coupled with fetchmail's ability to respond to the appropriate error messages, you can be assured of never seeing a spam from any address you put in the reject list.

The only thing that is missing, as mentioned previously, is the ability to allow sendmail to process the message further and generate an error message to the sender.

## C6. How can I do automatic startup/shutdown of fetchmail when I 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.

## T1. 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 setup 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 deliver 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.

## T2. How can I use fetchmail with exim?

By default, the exim listener enforces the the 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).

Fetchmail always passes fully qualified RCPT TO addresses. But 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.

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).

## T3. 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.

## T4. 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 intuitive. Use `forcecr'.

## R1. 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 the next question.

## R2. 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 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 recent 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.

## R3. 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 X2.)

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.

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.

## 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 by fetchmail, either).

## R5. 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 acknowledgement 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, POP3 has a design problem in that its servers mark 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 POP3 fetch options.

Solution: switch to an IMAP server.

## R6. Fetchmail dumps core when I use a .netrc file but works otherwise.

We have a report that under Solaris 2.5 using gcc-2.7.2, if fetchmail is compiled with -O or -O2, it segfaults on startup when reading a .netrc.

You can work around this by disabling optimization.

There may be an actual bug here that the optimizer exposes; the stack trace says the segfault is in free() and has all the earmarks of a heap- corruption screw. But the symptom doesn't reproduce under Linux with the same .fetchmailrc and .netrc.

## R7. All my mail seems to disappear after an interrupt.

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.

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 brfore 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 an QUIT -- this is a technical violation of the 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.)

## M1. I've declared local names, but all my multidrop mail is going to root anyway.

Somehow your fetchmail is never matching the hostname part of recipient names to the name of the mailserver machine. This probably means it is unable to recognize hostname parts as being DNS names of the mailserver, and indicates 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.

## 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 expiry 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 addess 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.

## 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 R2!) who solved this problem by removing the reference to -lresolv from his link line and relinking. Apparently in some recent 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 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 dames, 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

## X1. 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!

In versions up to 1.9.9 this led to pesky errors at some sites. Because of this, I hacked 2.0 to just use the calling user ID as the MAIL FROM address.

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.

## X2. 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.

## X3. My mail client can't see a Subject line.

First, see X2. 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.

## X4. 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 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.

## 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 doen'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.

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