Varnish 4.0.2 throwing 503s - Critical Production Issue

[Lasse Karstensen]

On Tue, Sep 01, 2015 at 05:32:01PM -0700, Ram Palagummi wrote:
> <table cellspacing="0" cellpadding="0" border="0"><tr><td valign="top"><div id='yahoo__compose_area' style="background-color:white; display:block; font-family:HelveticaNeue-Regular,Helvetica;"><br>We have been using Varnish 4.0.2 and noticing lots of 503s even when back end servers are available and healthy. We don't see any issues with network either. <div><br></div><div>FYI, the following are already set in our VCL</div><div><br></div><div>Connect_timeout = 120s</div><div>First_byte_timeout = 120s</div><div>Between_bytes_timeout = 120s</div><div><br></div><div>But we still see 503s, Is there anything else that must be set to resolve this issue?</div><div><br></div><div>Thanks</div><div>Ram</div><div><br><div><br><a href="https://yho.com/footer0">Sent from Yahoo Mail for iPhone</a></div></div></div><div id='yahoo__original_message'></div></html></td></tr></table>
> 

Please post your email as plain text and not HTML.

Having timeouts that high is usually a bad idea, as you don't get the
log segments back from the worker threads before the timeout goes off.
Two minutes is a long time to wait while debuging an issue.

To get help with this you need to extract varnishlog for the 503s and
post that.

-- 
Lasse Karstensen
Varnish Software AS