Re: timestamp monitoring + code simplification patch

[Christian Hopp]

On Thu, 28 Nov 2002, Jan-Henrik Haukeland wrote:

> Martin Pala <address@hidden> writes:
>
> > Hi,
> >
> > i wrote feature for monit to allow monitoring timestamp of file or
> > directory recently.
> >
> >
> > I need this feature to watch health of iPlanet Messaging server stored
> > process (it is critical) - this process periodicaly updates timestamp
> > of 3 independent state files. As soon as timestamp of any of these
> > files is older than expected, it signalizes, that one of tasks, that
> > stored deamon does failed and real hell is starting. New statement has
> > following syntax:
> >
> >
> >   TIMESTAMP object [operator] value [unit] [action]

And you can reuse code from the "resource" checks with this syntax.
Btw... what is your default unit?  And what about "absolute"
timestamps?

> Such functionality is not a big issue for me, but never the less it's
> an interesting feature and here's my +1 vote for including it in monit.

It's +1 with me, too... even if I have no use for it now... but wait...
you can misuse for some cron stuff.  If you want to update a file
every 5 minutes... disable the alert make stop to /bin/true and start
to the prog you want to start.  Thus, you can update gfx on your www
server and that stuff... cool. (-:

(...)

> Yet another thing, we should discuss the syntax. Up until know we have
> only had one major statement which is the 'check name with pidfile'
> and with option. This is going to be a stand-alone statement with the
> same scope as the check-statement.

The syntax is right now,

CHECK name PIDFILE path ...options... (1)

> I'm wondering if we should keep with the check idiom and we could also
> combine this with the new filesystem test and use something like
> (instead of IF TIMESTAMP and such):
>
> CHECK DEVICE NAME ..options..
> CHECK DIRECTORY NAME ..options..
> CHECK FILE NAME ..options..

If we want to be "compatible" with (1) we need the following,

CHECK name [PIDFILE|DEVICE|DIRECTORY|FILE] path ...options...

> and here are some examples combining it with your timestamp
> functionality:
>
> check file "/usr/iplanet/msg-ims1/config/stored.ckp"

CHECK iplanet_stored FILE "/usr/iplanet/msg-ims1/config/stored.ckp"

>     if timestamp  > 5 minutes  then alert martin
>     if size > 10Mb then alert hauk #New option
>     if deleted then alert address@hidden

> check directory "/foo/directory"

CHECK foo_dir DIRECTORY "/foo/directory"

>     if timestamp < 10 minutes then alert martin
>     if size > 100Mb then alert #New option
>     if deleted then alert address@hidden


> This one probably does not need a timestamp check?
>
> check device /dev/HDA1

CHECK mylittlebigharddisk DEVICE /dev/hda1

>     if used > 100Gb then alert martin or
>     if available < 100Mb then alert martin

And don't forget (I have heard of problems like this)..

      IF AVAILABLE < 1000INODES THEN ALERT MARTIN

esp. mail and news servers need that option!


And what about this?

     IF ERROR THEN ALERT martin

In case the device is not there any more (devfs -> plugging out the
device), not mounted anymore, access denied...?


Christian

-- 
Christian Hopp                                email: address@hidden
Institut für Elektrische Informationstechnik             fon: +49-5323-72-2113
TU Clausthal, Leibnizstr. 28, 38678 Clausthal-Zellerf.   fax: +49-5323-72-3197
                             pgpkey: https://www.iei.tu-clausthal.de/pgp-keys/