Re: [squid-users] Parent TCP connection failed

On 08/10/11 03:51, Artemis Braja wrote:
> Hello,
>
> I'm running two frontends instances on ports 3128 and 3129, and two
> backend instances on ports 4001 and 4002 on the same box, and
> loadbalancing between parents using carp.
> cache_peer localhost parent 4001 0 carp name=backend-1
> cache_peer localhost parent 4002 0 carp name=backend-2
>
> squid -v
> Squid Cache: Version 3.1.15
> configure options: '--enable-async-io' '--enable-linux-netfilter'
> '--enable-storeio=ufs,aufs' '--exec-prefix=/usr' '--bindir=/usr/sbin'
> '--libexecdir=/usr/lib/squid' '--enable-carp' '--enable-cache-digests'
> '--enable-removal-policies=lru,heap' --with-squid=/opt/squid-3.1.15
> --enable-ltdl-convenience
>
> After successfully starting all instances I see on the frontends
> cache.log:
> 2011/10/07 16:10:56| TCP connection to localhost/4001 failed
> 2011/10/07 16:10:56| TCP connection to localhost/4002 failed
> 2011/10/07 16:10:57| TCP connection to localhost/4001 failed
> 2011/10/07 16:10:57| TCP connection to localhost/4002 failed
> 2011/10/07 16:10:57| Detected DEAD Parent: backend-2
> 2011/10/07 16:10:58| TCP connection to localhost/4001 failed
> 2011/10/07 16:10:58| Detected DEAD Parent: backend-1
> 2011/10/07 16:11:19| temporary disabling (Service Unavailable) digest
> from localhost
> 2011/10/07 16:20:16| TCP connection to localhost/4002 failed
> 2011/10/07 16:25:20| temporary disabling (Service Unavailable) digest
> from localhost
>
> Because only backends are caching, not connecting to then all traffic
> from frontends is forwarded to the origin servers, making the storages
> useless.

Add no-digest to the cache_peer lines on the frontend. That will silence
the digest messages and make it a little bit longer before DEAD gets
triggered.

Check that your backend were actually finished loading their caches and
listening for new traffic before the frontend were connected to them.

Note that Squid-3.1 is IPv6-enabled software so "localhost" is probably
the IP address ::1. You may need to check your IPv6 firewall settings to
verify the layers can connect over localhost.

Amos

-- 
Please be using
   Current Stable Squid 2.7.STABLE9 or 3.1.15
   Beta testers wanted for 3.2.0.12