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Plesk 9.2.1 and Postfix not doing DNS Lookups

S

SaschaH

Guest
Hi all,

it seems that the Postfix Daemon isn´t able to perform DNS Lookups. Customers reporting, that they don´t receive E-Mails anymore. I´ve checked the Logs and in fact Postfix always reports a "reject from unknown [X.X.X.X]". When I do a nslookup manually on those logged IP-Addresses, there is no problem and the DNS works without any problem except Postfix.

As Plesk is using BIND as a Resolver, the /etc/resolv.conf contains:

search foo.bar
nameserver 127.0.0.1

Again. Everything regarding DNS Lookups works great. Only Postfix doesn´t perform DNS Lookups for some reason and i´m not able to track down the issue. Does someone have an idea of what the problem can be?

Thank you!
 
no dns lookups by postfix either

I am having the same problem. I understand postfix does not use the /etc/hosts file to query for the localhost. Would anybody know the solution to this problem?
 
Hello SaschaH,

use the resolvers of your ISP/Datacenter.

ex:

cat /etc/resolv.conf
nameserver 81.92.192.2
nameserver 81.92.193.1
nameserver 81.92.192.3

However past here your log ( /usr/local/psa/var/log/maillog ).

Regards,
 
this only happens with postfix

Hi our resolv.conf file is set up correctly, the proof of that is the everything works fine with qmail, which is what I ended up doing (going back to qmail), but I am really interested in using postfix

Thanks
 
Sure, here's some of it:
Jul 10 10:58:13 smtpgateway postfix/smtpd[14051]: connect from unknown[63.251.135.74]
Jul 10 10:58:13 smtpgateway postfix/smtpd[14058]: connect from unknown[127.0.0.1]
Jul 10 10:58:13 smtpgateway postfix/smtpd[14051]: NOQUEUE: client=unknown[63.251.135.74]
Jul 10 10:58:13 smtpgateway postfix/smtpd[14058]: D416A7490064: client=unknown[63.251.135.74]
Jul 10 10:58:13 smtpgateway postfix/smtpd[14058]: disconnect from unknown[127.0.0.1]
Jul 10 06:58:13 smtpgateway postfix/spawn[13975]: warning: command /usr/lib/plesk-9.0/postfix-queue exit status 255
Jul 10 10:58:15 smtpgateway postfix/smtpd[14050]: connect from unknown[61.105.207.26]
Jul 10 10:58:27 smtpgateway postfix/smtpd[13977]: connect from unknown[127.0.0.1]
Jul 10 10:58:28 smtpgateway postfix/smtpd[14050]: NOQUEUE: client=unknown[61.105.207.26]
Jul 10 10:58:28 smtpgateway postfix/smtpd[13977]: 010067490064: client=unknown[61.105.207.26]
 
I found something very odd. i was looking at the /etc/postfix/main.cf file and I found the mynetworks entry uncomented with two ips, one is of a domain I am using and the other is an ip I had white listed in the mail server configuration. Would not this place be for the DNS servers? I know for sure I did not make any edits to this file, so it must have happened when I installed the Plesk panel.
 
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