How can I check why a Varnish probe fails?

varnish
Gabriele Perego picture Gabriele Perego · Aug 5, 2013 · Viewed 14.4k times · Source

I'm used to run

varnishadm -T localhost:6082 debug.health

to check the backends health status, but how can I check why a probe fails in details (eg timeouts, wrong http status code)?

Answer

Ted Percival picture Ted Percival · May 3, 2016

In Varnish 4.0 you can see the status of all backends and their recent probe success rate with

varnishadm backend.list

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