[Xymon] Should a HTTP 304 response be green or yellow?

[J.C. Cleaver]

On Tue, October 6, 2015 6:46 am, Axel Beckert wrote:
> Hi,
>
> one our HTTP checks went yellow today because the Apache being tested
> responded with a "304 Not Modified" HTTP code, and the check went
> yellow.
>
> "304 Not Modified" is generally a valid HTTP answer which does not
> indicate a problem but rather a properly working server -- if the
> client provided the according meta information, namely either the
> If-Modified-Since or If-None-Match HTTP headers.
>
> But xymonnet doesn't seem to send either of them, at least according
> to a quick grep through the xymon's source code.
>
> So I think that if xymonnet receives a 304 reply, there must be
> something wrong on the server side (broken reverse proxy or similar),
> hence the yellow state is some kind of justified.
>
> What do others think about that topic?
>
> 		Kind regards, Axel Beckert

I'd consider it a valid use case for a yellow, since by construction
there's really no expectation that xymonnet would actually receive that,
as you said. (As opposed to a 301/2/3, which could be entirely reasonably
for a retrieval.)


On a related note, I'd been holding off on committing Mark's patch from
https://sourceforge.net/p/xymon/mailman/message/34420580/ until I had a
chance to go through the "extended" HTTP RFCs and make some sort of
red/yellow determination. If the community had an agreement on suitable
defaults, that would help.


Ultimately, making a default mapping of HTTP codes to each state via
config variable would make the most sense (sort of uplifting the
'httpstatus:' logic), since there'll be variation desired from site to
site. Performance impact does have to be considered for larger sites and
xymonnet runs, however.


-jc