[opensuse] postfix isn't accepting connections anymore. Any changes to postfix?
Dear list, I ran out of ideas. My postfix installation on a opensuse 10.0 isn't accepting connections anymore. Out of sudden!! I didn't change anything (last what I did was using the apt upgrades for apache and php the day before but there can't be any relation I guess). While port 25 is dead submission port 587 is working as expected. Log files are still growing since spammers were rejected (mail and mail.info). I tried everything I could think of (in my panic including a restart of the machine :-x) - turned firewall in yast on/off - tried with telnet remote and from localhost - googled the lines of the log files Is there anything recent I should know about postfix?? Is there a heavy spam attack? But it's not slow it isn't working anymore...Webserver and cyrus imap is running as it should. Thanks for any help. -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
Thu, 09 Aug 2007, by johannes.nohl@gmail.com:
Dear list,
I ran out of ideas. My postfix installation on a opensuse 10.0 isn't accepting connections anymore. Out of sudden!! I didn't change anything (last what I did was using the apt upgrades for apache and php the day before but there can't be any relation I guess). While port 25 is dead submission port 587 is working as expected. Log files are still growing since spammers were rejected (mail and mail.info).
Either it's not accepting connections, and thus not rejecting them either, or it is accepting connections and maybe rejecting (because of something you've changed). It can't be both.
I tried everything I could think of (in my panic including a restart of the machine :-x)
- turned firewall in yast on/off - tried with telnet remote and from localhost - googled the lines of the log files
http://www.postfix.org/DEBUG_README.html " When Postfix does not receive or deliver mail, the first order of business is to look for errors that prevent Postfix from working properly: % egrep '(warning|error|fatal|panic):' /some/log/file | more " Theo -- Theo v. Werkhoven Registered Linux user# 99872 http://counter.li.org ICBM 52 13 26N , 4 29 47E. + ICQ: 277217131 SUSE 10.2 + Jabber: muadib@jabber.xs4all.nl Kernel 2.6.20 + See headers for PGP/GPG info. Claimer: any email I receive will become my property. Disclaimers do not apply. -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
Thanks Theo for your fast answer.
I ran out of ideas. My postfix installation on a opensuse 10.0 isn't accepting connections anymore. Out of sudden!! I didn't change anything (last what I did was using the apt upgrades for apache and php the day before but there can't be any relation I guess). While port 25 is dead submission port 587 is working as expected. Log files are still growing since spammers were rejected (mail and mail.info).
Either it's not accepting connections, and thus not rejecting them either, or it is accepting connections and maybe rejecting (because of something you've changed). It can't be both.
I telnet the server on port 25. Now the so called banner should be sent. But it isn't. So no chance to drop HELO. And after a while the connection will be closed. -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
Johannes Nohl wrote:
Thanks Theo for your fast answer.
I ran out of ideas. My postfix installation on a opensuse 10.0 isn't accepting connections anymore. Out of sudden!! I didn't change anything (last what I did was using the apt upgrades for apache and php the day before but there can't be any relation I guess). While port 25 is dead submission port 587 is working as expected. Log files are still growing since spammers were rejected (mail and mail.info). Either it's not accepting connections, and thus not rejecting them either, or it is accepting connections and maybe rejecting (because of something you've changed). It can't be both.
I telnet the server on port 25. Now the so called banner should be sent. But it isn't. So no chance to drop HELO. And after a while the connection will be closed.
Please send output of "postconf -n". When you restart Postfix and try to send a mail, what do you see in the log? Please post the log lines. This is problably a DNS timeout problem. Postfix is trying to resolve the client ip and checks the reverse dns as well. Without working dns you will run into many problems. -- Sandy List replies only please! Please address PMs to: news-reply2 (@) japantest (.) homelinux (.) com -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
This is problably a DNS timeout problem. Postfix is trying to resolve the client ip and checks the reverse dns as well. Without working dns you will run into many problems.
Yesterday I added "disable_dns_lookups = yes" to main.cf without help. But today everything is running well. If it's about DNS (you are probably right) are there more than this switch. Thanks Sandy. -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
Johannes Nohl wrote:
This is problably a DNS timeout problem. Postfix is trying to resolve the client ip and checks the reverse dns as well. Without working dns you will run into many problems.
Yesterday I added "disable_dns_lookups = yes" to main.cf without help. But today everything is running well. If it's about DNS (you are probably right) are there more than this switch. Thanks Sandy.
Almost Everything that has to do with hostname resolution and transport decisions will depend on dns. That includes RBLs, connecting clients, sending mails to other hosts, but also checks like - reject_unknown_sender_domain - reject_unknown_recipient_domain - reject_unknown_client_hostname - reject_unknown_helo_hostname - reject_sender_mx_access ... A good reliable DNS resolution is a prerequisite for running a mailserver. -- Sandy List replies only please! Please address PMs to: news-reply2 (@) japantest (.) homelinux (.) com -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
I telnet the server on port 25. Now the so called banner should be sent. But it isn't. So no chance to drop HELO. And after a while the connection will be closed.
Sorry for the noise, after three days the problem is gone. Suddenly as it came. Don't know. Maybe a spam attack. Thanks Theo. -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
Fri, 10 Aug 2007, by johannes.nohl@gmail.com:
I telnet the server on port 25. Now the so called banner should be sent. But it isn't. So no chance to drop HELO. And after a while the connection will be closed.
Sorry for the noise, after three days the problem is gone. Suddenly as it came. Don't know. Maybe a spam attack. Thanks Theo.
Postfix does *not* fall over because of a "spam attack". It's designed to be able to handle 100s, or on very beefy hardware 1000s, of simultaneous connections per second I agree with the other repliers though, it was probably a DNS problem. One question: why didn't you post the output from the grep command as requested; do you really expect people to dig out an answer from their xtal bowls? Theo -- Theo v. Werkhoven Registered Linux user# 99872 http://counter.li.org ICBM 52 13 26N , 4 29 47E. + ICQ: 277217131 SUSE 10.2 + Jabber: muadib@jabber.xs4all.nl Kernel 2.6.20 + See headers for PGP/GPG info. Claimer: any email I receive will become my property. Disclaimers do not apply. -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
One question: why didn't you post the output from the grep command as requested; do you really expect people to dig out an answer from their xtal bowls?
I know. I started to anonymize the output of errs/warns/infos (I think people don't want me to send their e-mail-adress over the mailing list). Then the problem was gone out of sudden (as written in my last e-mail). That's why I did not send it. All I've read about DNS and postfix I could imagine that this was the problem. But I tried the "disable_dns_lookups = yes" switch (as far as I know it should stop all DNS queries). It didn't help... Thanks to all -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
participants (3)
-
Johannes Nohl -
Sandy Drobic -
Theo v. Werkhoven