Postfix can't resolve any DNS!

[ittec]

Hi

recently we discovered a strange behaviour on /usr/local/psa/var/log/maillog with Postfix as MTA on Plesk 9.0.1. It seems Postfix can't resolve DNS

Aug 7 08:02:09 dns2 postfix/smtpd[17849]: connect from unknown[127.0.0.1]
Aug 7 08:02:09 dns2 postfix/smtpd[17749]: connect from unknown[127.0.0.1]
Aug 7 08:02:09 dns2 postfix/smtpd[9467]: connect from unknown[127.0.0.1]
Aug 7 08:02:09 dns2 postfix/smtpd[17849]: 7B3B82FE30508: client=unknown[127.0.0.1]
Aug 7 08:02:09 dns2 postfix/smtpd[17749]: 7B7BA2FE30513: client=unknown[127.0.0.1]
Aug 7 10:02:09 dns2 before-remote[18046]: check handlers for addr:

Aug 7 08:06:26 dns2 postfix/smtpd[9457]: lost connection after DATA from unknown[123.26.34.72]
Aug 7 08:06:26 dns2 postfix/smtpd[9457]: disconnect from unknown[123.26.34.72]

Aug 7 08:06:28 dns2 postfix/smtpd[17883]: lost connection after RCPT from unknown[81.23.190.108]
Aug 7 08:06:28 dns2 postfix/smtpd[17883]: disconnect from unknown[81.23.190.108]

I don't know exactly if is a big deal or not, but we are having problems specially during our highest traffic hour, when customers can't connect through our smpt in any way. We don't know if back to Qmail...but I want to use Postfix it is possible to fix this issue.

Any idea will be wellcome.

Thanks

 

[lvalics]

I does not seems to me a DNS error. Better check the log, I think is an another issue.

 

[ittec]

Like what?

Hi lvalics

I really don't know if this is a serious issue or not, but I can't imagine another subject like DNS with a missage like:

Aug 11 09:30:16 dns postfix/smtpd[28444]: disconnect from unknown[85.172.31.182]
Aug 11 09:30:23 dns postfix/smtpd[28444]: connect from unknown[123.26.117.55]

Is continous. There are another problem showed in logs but I don't know if is related with Postfix and DNS

Aug 11 09:31:23 dns2 postfix/smtpd[28444]: sql_sqlite3 plugin: no result found
Aug 11 09:31:29 dns2 postfix/smtpd[29909]: sql_sqlite3 plugin: no result found

Is serious?

Thanks

 

[lvalics]

I think postfix greylisting, not sure.

 

[kanada]

Check all services work properly, many connections from localhost aren't weird (if your server wasn't hacked/compromised fo course).

Regards,
Alex

 

[ittec]

Thanks

Hi

I don't think server has been hacked. I hope so. It doesn't matter if connection was did from localhost or external, my doubt is with unknown in external ips. If this is normal or not.

The behavior still happening.

 

[kanada]

Seems you have problem with permissions in system for postfix user.

Please check if postfix work in chroot environment (you can see this in master.cf file).
After disable this option all will work properly.

Other way is configure postfix to work in chroot ;-)

Regards,
Alex