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Mail Problems - Reverse DNS for Different IP Missing, Causing Bounces

jola

Basic Pleskian
I am having problems with mail on my new plesk 10.1 installation:

I have two IP based sites setup in my plesk, lets call the two IP numbers IP_1 and IP_2. When I send out email from the first IP_1 site some foreign mail servers reject my messages and qmail tells me the reason is that I lack a reverse DNS entry for IP_2. Here is an an example of a bounce where I have replaved the real IP number with IP_1/IP_2. My original message was sent from IP_1 and bounced with a message back like this:

x.x.x.x does not like recipient.
Remote host said: 550-Inconsistent or no rDNS record for IP_2 (see RFC1912 2.1)
550-http://www.ietf.org/rfc/rfc1912.txt
550-Reverse DNS record and matching forward entry must exist.
550 => wrong configuration at sending server IP_2

Anyone have any idea what can be the reason for this? I don't understand how emails from IP_1 can in any way generate a bounce due to IP_2. IP_2 does indeed lack a reverse DNS entry right now, but how on earth can that affect emails sent from IP_1?

DNS and I have never been good friends :-(
 
Incorrect IP address - incorrect line in /etc/hosts

Replying to myself here. I have tried to debug this the whole day now :-/ I fixed the reverse DNS problem for IP_2. Now some of the servers that rejected my emails from IP_1 accept them. However, servers that use SPF still rejects my email. I don't think the missing reverse dns for IP_2 was the origin to my problems.

For some strange reason my plesk installation, which is running in a virtuozzo container, always sends emails from the IP number of one of the IP-based sites in plesk (IP_2). The server also incorrectly has this IP_2 set in /etc/hosts. The incorrect line has a warning above it that it is auto-generated, so I'm unsure about what to do about it.

My plesk installation (in a virtuozzo container) seems to use the wrong IP number when it sends mails. It only uses the IP number of one of the sites inside plesk.

Any clues how I can fix this?
 
same problem

hello, i have the same problem that you have and thinking about how to solve but nothing for the moment.

i have two IP adresses on the server. one shared, the other exclusive for a secured (ssl) domain. qmail is sending from two adresses and trend micro's firewalls check the reverse DNS records and don't allow the second IP address as sender.

how can you set up two different reverse DNS for the same server?
 
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