[Exim] exim behing iptables

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Hello –

I am running Exim 4.2 on a RH 7.2 machine. I use iptables with the input
chain set to drop and rules to open port 25 to all traffic, allow any
service on the machine to access dns, etc. I can receive mail with the drop
policy in place but when I try to send non local mail Exim times out. Do I
need to open additional ports for Exim? If yes, which ones? If no, any ideas
on why the time out?

Thank you.

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