A lot of TCP: time wait bucket table overflow in CentOS 6

Posted by divaka on Server Fault See other posts from Server Fault or by divaka
Published on 2012-11-17T17:59:50Z Indexed on 2012/11/17 23:05 UTC
Read the original article Hit count: 1497

Filed under:

linux

|

tcp

|

centos6

we have the following output from dmesg:

__ratelimit: 33491 callbacks suppressed
TCP: time wait bucket table overflow
TCP: time wait bucket table overflow
TCP: time wait bucket table overflow
TCP: time wait bucket table overflow
TCP: time wait bucket table overflow
TCP: time wait bucket table overflow
TCP: time wait bucket table overflow
TCP: time wait bucket table overflow
TCP: time wait bucket table overflow
TCP: time wait bucket table overflow

Also we have the following setting:

cat /proc/sys/net/ipv4/tcp_max_tw_buckets
524288

We are under some kind of attack, but we could not detect what cause this problem?

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