[Nagiosplug-devel] RFC: new style command arguments for thresholds

[Andreas Ericsson]

Ton Voon wrote:
> 
> Andreas disagrees with XML because of shell problems with "<" and ">". I
> guess this is for Nagios 1.x systems where perf data had to be sent via
> command lines. Since Nagios 2+ uses environment variables, this should
> be less of an issue.
> 

Perhaps, but there's also a limit on how much data you can chuck into the
environment. For the "small" plugins, I imagine this isn't a problem, but
for those the current perf-data output already works very nicely, so I'm
guessing this is for checking something like disk usage on systems with
loads and loads of mounted disks.


> Andreas disagrees with the choice of "/" as the separator in
> --metric=crit/warn and suggests comma instead. I want to avoid a comma
> because, in future, I can see ranges will be defined with comma to mean
> other ranges, such as current page ranges: 1-6,9. Also, I'd like to keep
> the crit and warn definition in the same syntax argument, rather than
> separating out to --metric-crit and --metric-warn. I'm all for a
> different delimiter if it makes sense and doesn't clash. I avoided
> semi-colon because of the shell meaning.
> 

I had assumed you wouldn't use ranges with crit/warn syntax, as those are
generally hard enough to read anyways, especially if you're going to use
multi-parameter ranges as suggested above.

You'll end up with command_line variables looking like this

	100/50!^15:25/^5:15,25:35

which is as readily readable as this little gem

	sed '1!G;h;$!d'

and definitely not something you want to find lurking at line 839 at when
you're looking for errors.


> 
> I'm starting to think that, with the Nagios/NRPE output limitations,
> that XML is too much right now and that we need to stick to the current
> output style. However, I think the warn and crit sections of the current
> perf data output is inconsistent to the point of being useless right
> now, but I would need some people from the graphing teams to tell me
> what they think. I'll drop the emails to various lists.
> 

I've got a pretty good feeling about what they'll say:
"You better make this change on a flag-day, cause everything will break".

Otoh, I assume this would mean a 2.0 release of the plugins, so that'd be
a sort of flag-day in and of itself.

-- 
Andreas Ericsson                   andreas.ericsson at op5.se
OP5 AB                             www.op5.se
Tel: +46 8-230225                  Fax: +46 8-230231