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I currently have a server running "Ubuntu Server 12.04.1 LTS" installed with

  • Postfix
  • Bind 9 (Slave)

The postfix cannot seem to resolve my internal IPs to Name Server (PTR) entry I have within bind9 settings.

eg. I am wanting DNS to resolve to by using a bind9 " record in my maste/slave folder which contains a record like this:-

$GENERATE 1-254 $       PTR    priv-000-$

I have checked using nslookup & dig, both work fine without any issues resolving IP to the name.

I have made sure that the name server is the first in the list:-


I have also tried also going into /etc/postfix/ and added

smtp_host_lookup = native,dns

I am only using this system to relay emails to my exchange server & that works perfectly but try to get this name resolving issue fixed.

Not sure if this is important to anyone but if I remove "native" I cannot relay emails to my exchange server.

I know I can use hosts & that appears to work fine but was really wanting to keep the same setup & not have to manually enter every single IP address into the hosts file.

Hopefully someone with better linux knowledge can help me as I have wasted nearly 6 hours on trying to resolve this issue with any success.

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