X-Git-Url: http://pileus.org/git/?a=blobdiff_plain;f=fetchmail-FAQ.html;h=4f66e801bdf3ead142f5269791e8cffa65e59dcc;hb=9ef5bbefc9478fb6ad31a3c9d0a4e93397ff7e54;hp=010275c12ccf1ed6836f0a4b5b3df196337bb513;hpb=f35ea15b76a5e1883e0c9fe259a3572f8d75bea7;p=~andy%2Ffetchmail diff --git a/fetchmail-FAQ.html b/fetchmail-FAQ.html index 010275c1..4f66e801 100644 --- a/fetchmail-FAQ.html +++ b/fetchmail-FAQ.html @@ -10,7 +10,7 @@
Back to Fetchmail Home Page | To Site Map - | $Date: 1998/05/16 19:17:42 $ + | $Date: 1999/08/21 06:04:18 $ |
+ +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.
@@ -150,7 +180,7 @@ 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 find +http://www.tuxedo.org/~esr/fetchmail. You can also usually find both in the POP mail tools directory on Sunsite.
@@ -169,6 +199,7 @@ bugs, please include the following:
-It is helpful if you include your .fetchmailrc, but not necessary -unless your symptom seems to involve an error in configuration parsing.
+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 +(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 @@ -192,9 +225,12 @@ 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 on is almost always useful. +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.
+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 @@ -226,7 +262,7 @@ 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
+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
@@ -240,7 +276,7 @@ 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 or involve me in large +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 @@ -266,19 +302,20 @@ in the Subject line unsubscribes you, and "help" returns general list help)
+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, -and will be an invited presentation at Usenix and UniForum '98. The -folks at Netscape tell me it helped them decide to 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).
+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.
@@ -286,28 +323,50 @@ on the Web with a search for that title.
+ +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 oughtright 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.
+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).
- -If you have the option, we recommend using or installing IMAP4; 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.
+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 and Cyrus products. UW IMAP is the reference -implementation of IMAP.
+href="http://www.imap.org">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. +
+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
+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. 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.
+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 @@ -369,7 +430,7 @@ 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 T7 for details.
+href="#S3">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 @@ -379,10 +440,12 @@ 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 (February 1998) no OTP or APOP-like +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 4.1-BETA.
+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 @@ -396,7 +459,7 @@ 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 ITAR restrictions.)
+(One important win of OTP is that it's not subject to EAR restrictions.)
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 your client machine's -hostname.
+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).
-This, however, can create problems when fetchmail is running in daemon +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.
@@ -427,7 +491,7 @@ 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.
+multihomed sites. See C3.
I recommend against trying to set up the interface
option
when initially developing your poll configuration -- it's never
@@ -464,10 +528,10 @@ 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.)
+site.
The specific recipe for using fetchmail with a firewall is at T10
+href="#K1">K1
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 +href="ftp://prep.ai.mit.edu/ftp/pub/gnu">flex and use that. All will be happier.''
-I couldn't have put it better myself, and aren't going to try now.
+I couldn't have put it better myself, and ain't going to try now.
+ +
+ +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.
+ +
+ +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.
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.+
via
' option was introduced, I realized
@@ -572,27 +671,26 @@ Do similarly for any `monitor
' or `batchlimit
' options
+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 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.
+The lexical analyzer in 5.0.6 and beyond is smarter and assumes +any token following "username" or "password" is a string.
+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.).
-You can work around this easily. Just put string quotes around your +Upgrade to a 5.0.6 or later fetchmail, or 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.
-
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 +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.
+`default' aliases (itz->itz) don't count. They should.
Answer:
@@ -713,7 +811,7 @@ more complicated or both.
+Some people start up and shut down fetchmail using the ppp-up and +ppp-down scripts of pppd.
+
+
- -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.)
+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.
-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": - -
-
+The table itself uses email addresses, domain names, and network +numbers as keys. For example,
-command="socket localhost 110",no-port-forwarding 1024 ...... +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)
-where "1024
......" is the content of noddy's identity.pub file.
--#! /bin/sh -exec ssh -q -C -l your.login.id -e none mailhost socket localhost 110 --
-1234 stream tcp nowait noddy /usr/sbin/tcpd /usr/local/bin/ssh.fm --
- -
- -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! - -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:
+To actually set up the database, run
- "571 unsolicited email is refused" +makemap hash deny <deny+in /etc/mail.
-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.
+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!!!
-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.
-
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
@@ -977,6 +975,21 @@ 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: $u ++ +and declare `
envelope "Delivered-To:"
'. This will cause the
+mailserver's sendmail to reliably write the appropriate envelope
+address into each message before fetchmail sees it, and tell fetchmail
+which header it is. With this change, multidrop mode should work
+reliably even when the Received header omits the envelope address
+(which will typically be the case when the message has multiple
+recipients). +
- + To use this line you must:
- | ../bin/qmail-inject -a -f"$SENDER" "${LOCAL#mbox-userstr-}@$HOST}" + | ../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 @@ -1049,11 +1069,24 @@ from the local user name.
-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).
+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:
-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
@@ -1089,7 +1122,7 @@ 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
+it is an smail `feature' and has been reported to the maintainers
as a bug.
Very recent smail versions require an -smtp_hello_verify
@@ -1111,17 +1144,49 @@ using sendmail instead.
The Lotus Notes SMTP gateway tries to deduce when it should convert \n -to \r\n, but its rules are not intuitive. Use `forcecr'.
+to \r\n, but its rules are not the intuitive and correct-for-RFC822 +ones. Use `forcecr'.
+
+ +
+ +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.
+ +
+ +
-Fetchmail works with M$ Exchange, despite this braindamage. Two +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 @@ -1129,11 +1194,62 @@ 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).
-If you want these fixed, go bug the Evil Empire. Or, better yet, -install a real operating system on your mailserver and run IMAP.
+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:
+ +
+ +
+KEY_LOCAL_MACHINE\System\CurrentControlSet\Services\MsExchangeIs\Parameters +System\Pop3 Performance ++ +
+ +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.
-Give your RPA pass-phrase in lower case as your password. Add +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, it will query the server to see if it +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 verbose output of Fetchmail will show +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 ++
+ +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 ++ +
+ 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.
+ +
-No special configuration is required, but OpenMail has 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.
+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.
+ +
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.)
+ +
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.
+POP (or preferably IMAP) server that isn't brain-dead. OpenMail's +project manager claims these bugs have been fixed in 6.0
+ +
+ +This is a customer lock-in tactic; we recommend boycotting MSN as the +only appropriate response.
+ +
fetchall
+flag to ensure that it's recovered on the next cycle.+ +
@@ -1177,7 +1433,7 @@ gave us the following recipe:
want the "runsocks" program.
export SOCKS5_SERVER=socks.my.domain.com@@ -1190,8 +1446,35 @@ gave us the following recipe:
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.
+ +
+ +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.
+
-To use fetchmail with network security (read: IPsec), you need a system that +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 @@ -1229,14 +1512,190 @@ http://www.bieringer.de/linux/IPv6/IPv6-HOWTO/IPv6-HOWTO.html
+ +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": + +
+
+command="socket localhost 110",no-port-forwarding 1024 ...... ++ +where "
1024
......" is the content of noddy's identity.pub file.
++#! /bin/sh +exec ssh -q -C -l your.login.id -e none mailhost socket localhost 110 ++
+1234 stream tcp nowait noddy /usr/sbin/tcpd /usr/local/bin/ssh.fm ++
+ +For yet a third recipe, see Secure POP via SSH mini-HOWTO.
+ +
+ +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.
+ +
+ +
+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.
+ +
+ +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.
@@ -1284,15 +1743,21 @@ look at /etc/resolv.conf
; it should say something like
so your /etc/hosts
file is checked first. If you're
-running GNU libc6, check your /etc/nsswitch
file. Make
+running GNU libc6, check your /etc/nsswitch.conf
file. Make
sure it says something like
- order hosts,bind + hosts: files dnsagain, 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 @@ -1303,7 +1768,7 @@ linked only if it is actually needed. So under Linux it won't be, and this particular cause should go away.
@@ -1318,7 +1783,7 @@ match what you sent, then fetchmail or something on the server is broken.
flex
@@ -1334,7 +1799,7 @@ href="http://www.gnu.ai.mit.edu/order/ftp.html">mirror site
will help you get it faster.
@@ -1347,26 +1812,12 @@ 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).
+directly by fetchmail, either).
- -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.
- -
@@ -1378,14 +1829,14 @@ fetchmail with -N and an ampersand to background it.
This should not happen under Linux or any truly POSIX-conformant Unix.
/sbin/ifconfig
. If it's over 600, change it in your PPP
@@ -1397,6 +1848,39 @@ option values that work:mru 552 +
+ +
+ +
+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. +
+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
@@ -1426,12 +1911,12 @@ 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
+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 +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 @@ -1442,30 +1927,35 @@ order to avoid a `lock busy' error.)
-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.
+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 POP3 fetch options.
+Workaround: add the `fetchall
' keyword to your fetch options.
-Solution: switch to an IMAP server.
+Solution: switch to an IMAP4 server.
+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
@@ -1478,6 +1968,9 @@ 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.
+
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). +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
@@ -1510,7 +2003,7 @@ in a `here
' list before it will do multidrop routing.
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).
+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 @@ -1537,7 +2030,7 @@ If you use sendmail, you can check the list expansion with 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 -recent Linux distributions the libc bind library version works +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
@@ -1551,7 +2044,7 @@ 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,
+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.
@@ -1607,9 +2100,46 @@ 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++inside pop3 server with fetchmail and sendmail 8.83
+ +
+
+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
'.
+
+
+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.
+
- mda "cat >MBOX" keep fetchall + mda "cat >MBOX" keep fetchall-This will capture exactly 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 changes due to the
-forcecr
and stripcr
options. MBOX will in fact
-contain what programs downstream of fetchmail see.
+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 @@ -1748,10 +2279,31 @@ 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. 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. +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. + +
+ +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.
-
- -If your POP3 server fails to sanity-check TOP requests and clip them at -the next end-of-message, it will fetch the entire tail of the mailbox -starting with the current message. The qpopper 2.41 beta 1 server is -known to have this bug (though the qpopper 2.2 found on many Unixes -does not). It's been reported to me that the logic changed in 2.3.
-
-To work around it, set the fetchall
option. Under POP3
-only, this now has the side effect of forcing RETR use.
- -(It is possible this tip is no longer necessary. At least one tester -has claimed that the bounds check works but was fooled by an overflow -condition in the TOP argument. Decrementing the argument may have -fixed this.)
-
According to the POP3 RFCs, deletes aren't actually performed until you issue the end-of-session QUIT command. Fetchmail cannot fix this, -it takes cooperation from the. server. There are two possible -remedies:
+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 @@ -1875,17 +2405,17 @@ the calling-user ID. So if your SMTP listener isn't picky, the log will look right.
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 FQDN 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.
+/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)
.
@@ -1911,11 +2441,23 @@ differences between the remote-fetch protocols it uses.
Re-ordering messages is a user-agent function, anyway.
+
+
Back to Fetchmail Home Page | To Site Map - | $Date: 1998/05/16 19:17:42 $ + | $Date: 1999/08/21 06:04:18 $ |