[Varnish] #554: Backend Poll uses User-Agent for filtering

Varnish varnish-bugs at projects.linpro.no
Tue Sep 15 12:01:40 CEST 2009

#554: Backend Poll uses User-Agent for filtering
 Reporter:  mbm          |        Owner:  phk  
     Type:  enhancement  |       Status:  new  
 Priority:  normal       |    Milestone:       
Component:  varnishd     |      Version:  trunk
 Severity:  normal       |   Resolution:       
 Keywords:               |  
Comment (by mbm):

 Hi Poul-Henning,

 Thanks for replying. In my experience with other loadbalancer/proxies
 (ZXTMs in particular), you want to be able to filter out the healthchecks
 from your main logs (maybe not from your debug/attack logs). Obviously,
 you can't filter on IP address, because all the requests will also come
 from those IPs - although you can filter on an X-Forwarded-For: or
 similar. If you have a sensible polling interval for making the site high-
 availability (ie on the order of ~1min), then the number of hits to any
 single backend from the poller can be comparatively high. I found it was
 worth filtering out nagios healthchecks and zxtm healthchecks from our
 backends so that our main apache logs contained meaningful hits. When I
 moved to Varnish (at a different place, with slightly different
 requirements). I found that we needed something similar, hence writing
 this patch (and the other one in #481), which helped us to see when badly-
 behaved clients of our service were hitting us very hard.

 I'd certainly be interested in other people's feedback too, and it's
 useful to know that you considered this and I now understand to some
 extent why you didn't include it.



Ticket URL: <http://varnish.projects.linpro.no/ticket/554#comment:2>
Varnish <http://varnish.projects.linpro.no/>
The Varnish HTTP Accelerator

More information about the varnish-bugs mailing list