Sunday, April 19, 2015

Detect missed executions with OpenNMS

Everyone knows that OpenNMS is a powerful monitoring solution, but not everyone knows that since version 1.10 circa it embeds the Drools rule processing engine. Drools programs can then be used to extend the event handling logic in new and powerful ways.

The following example shows how OpenNMS can be extended to detect missed executions for recurring activities like backups or scheduled jobs.

Saturday, April 18, 2015

9 months with WIFIWEB

WIFIWEb is a local WDSL internet provider. Since I moved last year I have been a customer with their WDSL Max 10 profile.

This is the pingdom report for the last 9 months:

Applications sensitive to latency and micro-interruptions (like Remote Desktop) would from time to time drop the connection.

Bandwidth-wise results varied over the period, but except for one time when I had to call to fix a performance issue, the experience was pretty smooth with a download speed consistently in a 6~8 Mb/s window.
The 1Mb upload speed was always achieved.

Call quality using free VOIP softphones (sflphone or linphone) was generally bad, but I dont't know how much the fault lies with software or the connection.

Verdict: recommended.

Tuesday, April 14, 2015

RUNDECK job maintenance

Learn more about Rundeck.

Now that I have a fair number of jobs scheduled by Rundeck, how do I periodically prune the job execution history and keep only the last, say, 30 executions for each job?

Thursday, April 02, 2015

OpenNMS performance: tune Jrobin RRD file strategy

One of the nice aspects of OpenNMS is that, out of the box, it will collect a lot of data from most snmp-enabled resources. The downside is that such collection is I/O heavy (iops, not throughput).

Even on moderate installations with hundreds of nodes it is enough to swamp even the fastest disk subsystem (except for those with controllers supported by large write caches). A symptom is that I/O wait will be quite high on the opennms box itself.
I/O Wait before and after switch jrobin backend from FILE to MNIO