RE: [squid-users] Detected DEAD parent

On Fri, 6 Aug 2004, SXB6300 Mailing wrote:

> RH9 and squid 2.5S1. Too give a little more detail, all the squid proxies (parent
> and child) arrive on the same switch, so I really don't think it's a network issue.

If you see TCP connection failed messages then there is
very few possible causes:

   a) The peer is not running, either due to manual action or unexpected
restart. Seen in cache.log.

   b) The peer is not accepting any new connections due to running out of
filedescriptors. Seen in cache.log.

   c) Network connectivity is poor causing a lot of dropped packets. For
example if full/half duplex negotiation between server and switch is
wrong or bad cables. Usually seen in ping as packet loss but easier to
detect by network testing (netperf or similar).

   d) SYN backlog is full on the peer, possibly from someone SYN flooding
it or if there is very many dialup / wan type clients accessing it (large
latency client<->server). Not easily seen unless it gets very far where
the kernel may warn about a possible SYN flood..

Regards
Henrik
Received on Fri Aug 06 2004 - 04:53:17 MDT