Re: OT: Munin (was Re: Determining server load from client)

["CAJ CAJ" <pguser@xxxxxxxxx>]

On 3/21/07, Erik Jones <erik@xxxxxxxxxx> wrote:

On Mar 21, 2007, at 4:13 PM, Tobias Brox wrote:

[Erik Jones - Wed at 09:31:48AM -0500]

I use cacti (http://cacti.net) which does the same thing that munin  

does but in php instead.  Here's what I use to db stats to it (again,  

php):

I haven't tried cacti, but our sysadm has done a little bit of research

and concluded "cacti is better".  Maybe some day we'll move over.

Munin is generating all the graphs statically every fifth minute, while

cacti generates them on demand as far as I've understood.  The munin

approach is pretty bloat, since one usually would watch the graphs much

more seldom than what they are generated (at least, we do).  That's not

really an argument since CPU is cheap nowadays - but a real argument is

that the munin approach is less flexible.  One would like to adjust the

graph (like, min/max values for both axis) while watching quite some

times.

Well, by "default", Cacti polls all of the data sources you've set up every five minutes as well as that's how the docs instruct you to set up the cron job for the poller.  However, with a little understanding of how the rrdtool rras work, you could definitely poll more often and simply edit the existing rras and datasources to expect that or create new ones.  And, yes, the graph customization is pretty cool although for the most part the just map what's available from the rrdtool graph functionality.  If you do decide to set up Cacti I suggest you go straight to the faq section of the manual and read the part about going from a simple script to a graph.  The main manual is almost entirely centered on the built-in networking ( e.g. snmp) data sources and, as such, doesn't do much for explaining how to set up other data sources.

Has anyone had experience setting up something similar with Nagios? We monitor servers using nagios and not having to install additional software (cacti/munin) for postgres resource usage monitoring would be great.

Thanks in advance!