Connections time out before proxy_connect_timeout

John Arundel john at
Thu Sep 1 08:38:58 UTC 2011

On Wed, Aug 31, 2011 at 6:07 PM, Maxim Dounin <mdounin at> wrote:
> Connect timeout is limited by your OS's SYN retransmit count limit
> and timeout.  Under FreeBSD it's 75s by default (3 retransmits
> with exponential backoff: 3s + 6s + 12s + 24s), under Linux it's
> looks like something about 20s by default.  Looks like you are
> hitting this limit.
> The only way to enlarge this limit is to tune OS, e.g. on Linux
> try adjusting net.ipv4.tcp_syn_retries sysctl.

Yes, that fixed it. Thanks a lot!

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