Re: Interesting ipchains Challenge

paul_at_atom.sbrk.co.uk
Date: 12/30/04


Date: 30 Dec 2004 09:45:21 GMT

In article <1104389091.407835.6540@z14g2000cwz.googlegroups.com>, Linux-Mike wrote:
> For traffic coming in on port 25, accept the packet locally, untouched,
> and deliver it to the SMTP Daemon. Additionally, take all data coming
> in on Port 25 to my IP address (10.1.1.1) and send a copy of it out,
> changing the destination IP address from 10.1.1.1 to 10.1.1.2 (the test
> server).

TCP utilises handshaking, acknowledgments, retransmission, window sizing and
all sorts of things that are not going to make any implementation of this
reliable.

Maybe you could either use a proxy that receives the mail and distributes
it to multiple servers, or just use something like rsync to keep the mail
spools on both systems identical.

Paul



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