Tuesday, December 1, 2009

Munin 1.4.0 released

A bit late, but time ran out on Friday: On Friday we released Munin 1.4.0 to the world! It has been 2 months of work after many years of ..., let's call it preparation.

There is a ChangeLog and an announcement.

The most striking at first glance will perhaps be the new look: nicer html styling and new graph colours with better contrast than in the 1.2 series. Besides there has been some focus on scalability and security besides bug fixing. There are more than 200 closed tickets in the 1.4.0 milestone.

In the scalability department there are such easy (and obvious) wins as running multiple rrd-graph instances in parallel; these days you hardly find a computer without multiple cores. Let's use them! This is tunable through "max_graph_jobs" in munin.conf (will be in 1.4.1, there is a bug preventing the keyword from working in 1.4.0 *blush*). The default is up to 6 parallel rrd-graph jobs.

Another scalability feature is "multigraph", a feature that allows one plugin to create multiple graphs. This makes it practical to graph 48 port switches, and due to another change this is presented as "drill down" graphs: One graph shows the summed traffic on all ports of the switch, and if you click that you'll be transported to a sub-page where you can see traffic on each of the ports. Multigraph is usefull enough, and novel enough that I will write another blog post about it, in the mean time you can study to plugins if you are interested: snmp__if_multi and multigraph_tester. The last one contains some explanatory text, the first one does not ;-) This feature I optimistically call "MRTG-killer". I hope Tobi Oetiker does not hate me for that, after all Munin relies very heavily on his excellent RRD tool for storage and graphing.

For security we have SSL (TLS) support so you can not only encrypt the traffic between the munin-master and the nodes, you can also use certificates for authentication if you want.

We'll get back to more on Munin 1.4, of this you can be sure.