Issues with SYN on Lenny
Seeing a strange problem exhibited after a recent dist-upgrade of an
We see connections hanging when connecting to port 25 running on the
2.6.26 kernel version.
Running a tcpdump on the server shows that a syn packet is received, but
there's no ack or anything. Using the etch kernel doesn't cause this
issue either, which negates any issue with exim, iptables or named and
I'm wondering if there's been any changes to the tcp/ip stack or the way
the kernel handles syn cookies etc..
The server is under heavy utilization, so I'm wondering if we're
tripping an arbitrary value somewhere in /proc ?
Any tips greatly appreciated!
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