A huge amount of "sonewconn: pcb 0xfffffe0053916dc8: Listen queue overflow: 193 already in queue awaiting acceptance" in logs recently (9-STABLE)
andre at freebsd.org
Thu Jul 25 12:51:31 UTC 2013
On 25.07.2013 12:46, Lev Serebryakov wrote:
> Hello, Freebsd-net.
> I have 9.1-STABLE r253105 system, which started to flood logs with
> "sonewconn: pcb 0xfffffe0053916dc8: Listen queue overflow: 193 already in
> queue awaiting acceptance" messages (there are thousnds of it, if you take
> "last message was repeated 600 times" in account).
> Nothing was changed in settings for long time.
> How could I determine, which connections (listen port, at least) cause
> these messages?
This means the rate of incoming connection attempts is grater than the speed
of the application accepting them. Typically you either suffer from a DoS
attack or your server is undersized for the amount of traffic it is receiving.
A change to rate-limit the number of these messages is in the works to prevent
it filling from the logs too fast.
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