Hi Daniel,
Op 21-11-2017 om 14:20 schreef Daniel Schneller:
On 21. Nov. 2017, at 14:08, Lukas Tribus <lu...@ltri.eu> wrote:
[...]
Instead of hiding specific errors counters, why not send an actual
HTTP request that triggers a 200 OK response? So health checking is
not exempt from the statistics and only generates error statistics
when actual errors occur?
Good point. I wanted to avoid, however, having these “high level” health checks
from the many many sidecars being routed through to the actual backends.
Instead, I considered it enough to “only” check if the central haproxy is
available. In case it is, the sidecars rely on it doing the actual health
checks of the backends and responding with 503 or similar, when all backends
for a particular request happen to be down.
Maybe monitor-uri perhaps together with 'monitor fail' could help ?:
http://cbonte.github.io/haproxy-dconv/1.8/snapshot/configuration.html#4.2-monitor-uri
It says it wont log or forward the request.. not sure but maybe stats
will also skip it.
However, your idea and a little more Googling led me to this Github repo
https://github.com/jvehent/haproxy-aws#healthchecks-between-elb-and-haproxy
where they configure a dedicated “health check frontend” (albeit in their case
to work around an AWS/ELB limitation re/ PROXY protocol). I think I will adapt
this and configure the sidecars to health check on a dedicated port like this.
I’ll let you know how it goes.
Thanks a lot for your thoughts, so far :)
Daniel
Regards,
PiBa-NL / Pieter
