Linux - NetworkingThis forum is for any issue related to networks or networking.
Routing, network cards, OSI, etc. Anything is fair game.
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It seems that sendmail, once every 5 minutes or so will try and initiate a TCP connection with my firewall.
My firewall Log reports : Denied TCP connection from 10.x.x.x , 25. to 10.x.x.x 1028 where the first ip address is my mail server/port number and the second ip address is the firewall and the port number my mail server tried to connect on.
Why in the world would sendmail be trying to initiate tcp connections with my firewall?
For information sake: the mail server is behind the firewall running RedHat ES 3.0 kernel 2.4.21-4 (I know out of date). The version of sendmail I'm running is 8.12.10/8.12.10
Originally posted by bleunuit This is an odd problem I seem to be having.
It seems that sendmail, once every 5 minutes or so will try and initiate a TCP connection with my firewall.
My firewall Log reports : Denied TCP connection from 10.x.x.x , 25. to 10.x.x.x 1028 where the first ip address is my mail server/port number and the second ip address is the firewall and the port number my mail server tried to connect on.
Why in the world would sendmail be trying to initiate tcp connections with my firewall?
Actually, if the source port is 25, then this would be the reply packet (ack). So it looks like your firewall initiated the port 25 connection to your mail server, but your mail server could not reply (ack).
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