[Xymon] How to fine-tune limits for filesystem tests?

[Mike Burger]

> All -
>
> A couple of questions re: the analysis.cfg file and its syntax for the
> "DISK" test:
> *       The "U" suffix for warning / panic thresholds refers to *minimum*
> values for free-space available on the indicated file system, correct? In
> other words, the amount of free space has to fall below the indicated
> number of KB, right?
> *       What we want is to alert when a combination of thresholds are in
> effect: the file systems are both (a) above a certain percent full, and
> (b) less than a certain amount of free space (in blocks, megs, whatever).
> How would I combine the two types of tests?
>
> Thanks!

You are correct...the U parameter is based on blocks.

If you're looking at an individual filesystem, I believe that the only way
to "combine" these two parameters will be to create a custom script checks
your free space and reports it back to Xymon.

Now, here's the thing...you can have certain filesystems that are reported
based on actual free space (U parameter) and others, or even the default
for the rest, that can be reported based on percentages.

I'm doing exactly that. My thought is that default thresholds like 90%
yellow and 95% red are great for smaller filesystems...but to be quite
honest, 95% full on a 500G filesystem is a far cry from being 95% full on
a 5G or even a 500M filesystem.

As a result, for my larger filesystems, I choose to use a U based
threshold, and then use the 90/95% thresholds for the rest.

So, if you're ok with "combining" these tests based on a filesystem by
filesystem case basis, as I've done, you can do so like so:

HOST=somehost
        DISK    %^/da[0-9][0-9] 4194304U 3145728U
        DISK    /dbdump 6291456U 4194304U
        DISK    * 90 95

In the above, any filesystem that starts with /da (I have /da01 thru /da27
at present) yellow alarms under 4G free and red alarms under 3G free.
/dbdump yellow alarms under 6G and red alarms under 4G.

All other filesystems yellow alarm under 90% and red alarm under 95%.

I hope this helps.