Sporadic 503 errors with 3.0.2

Harri.Paivaniemi at tieto.com Harri.Paivaniemi at tieto.com
Mon Oct 31 05:37:38 CET 2011


Stupid guestion: Are you sure that the backed is healthy from the LB's point of view when this 503 appears? I mean if the LB is struggling with the probe sometimes...

You could also try to change to lb-director in loadbalancer to something else (I guess you are using RR) and ensure that you have no stickyness in this backend farm configured.


From: varnish-misc-bounces at varnish-cache.org [varnish-misc-bounces at varnish-cache.org] On Behalf Of Bryan Stillwell [bstillwell at photobucket.com]
Sent: 31 October 2011 5:40
To: varnish-misc at varnish-cache.org
Subject: Re: Sporadic 503 errors with 3.0.2

On Fri, Oct 28, 2011 at 12:41 AM, Tollef Fog Heen
<tfheen at varnish-software.com> wrote:
> ]] Bryan Stillwell
> | It looks like backend_fail numbers line up with what I'm seeing.  Any
> | suggestions on figuring out what is failing?
> My first guess would be you hitting connect_timeout, try increasing that
> and see if the rate changes?

Thanks for the response, but unfortunately that setting didn't have
any noticeable effect on the number of backend failures.

However, it did get me re-evaluating whether or not the problem
actually existed between varnish and the web servers.  Out of the
switches, networking cables, and load balancers, I decided to try
removing the load balancers today (since I was planning on doing that
anyways).  Once I did, the number of backend failures and 503
responses dropped to zero!  :-)


varnish-misc mailing list
varnish-misc at varnish-cache.org

More information about the varnish-misc mailing list