Can I change the update interval for munin graphs?

Question

I want munin to display a graph every two minutes to increase the level of detail. There are some links indicating that its somehow possible with munin 2.0, any idea how?

Answer 1

I have not tried, but this question in the FAQ suggests that you cannot:

Munin runs on an interval every five minutes (* / 5) on default Debian systems. Is it possible to change this interval to an arbitrary value?

Just edit the /etc/cron.d/munin file.

However, this will not change the details of Munin (or, rather, RRD); all RRD files are created to create averages in 5 minutes, and no matter how often you update RRD files, the result will not be (much) different. A change to this (default) behavior was suggested in Ticket No. 5.

However, if you look at ticket number 5 , the last message (closing):

the current trunk fully supports custom update_rate and accordingly increases the resolution of .rrd files.

So, if you are using a fairly recent version of munin, it might be worth a try.

Answer 2

Munin data capture resolution increases at the plugin level , not at the munin kernel level. This means that you cannot just change the entire installation to increase resolution. Instead, each plugin should be modified independently.

Two critical plugin configuration values ​​that determine resolution are

graph_data_size update_rate # in seconds 

• graph_data_size defines the size and structure of the RRD file used to store captured data.
• update_rate indicates how often new data is expected.

Since cron has a lower limit of one minute as its maximum resolution, this is easiest to achieve. Just update cron to run every minute and reconfigure the plugin to include these values.

 graph_data_size custom 1d, 1m for 1w, 5m for 1t, 15m for 1y update_rate 60 

Minute resolution requires caching of point-by-point data between cron runs and implementation time data (seconds from the epoch). I will detail these three posts:

http://software.danielwatrous.com/understanding-munin-plugins/

http://software.danielwatrous.com/increase-munin-resolution-to-one-minute/

http://software.danielwatrous.com/increase-munin-resolution-to-sub-minute/

Answer 3

Munin uses the cron job to run itself every 5 minutes by default. You can change it in crontab. On my CentOS system, it is located in /etc/cron.d/munin and looks like this:

 # # cron-jobs for munin # MAILTO=root */5 * * * * /usr/bin/munin-cron 

I changed it in the past to

 */1 * * * * /usr/bin/munin-cron 

However, since the monitoring system is Amazon AWS, I do not need Munin, which often now keeps it for 10 minutes on the servers where I use them.

Answer 4

zeeshan said:

Munin uses the cron job to run itself every 5 minutes by default. You can change it in crontab. On my CentOS system, it is located in /etc/cron.d/munin and looks like this:

#

cron-jobs for munin

#

MAILTO = root

* / 5 * * * * / usr / bin / munin-cron

I changed it in the past to

* / 1 * * * * / usr / bin / munin-cron

However, since the Amazon AWS monitoring system I do not need Munin, which often and now I keep it in 10 minutes on the servers where I use it.

You are about a munin server because munin-agent does not have cron jobs. Your graphs will not take a step less than 5 minutes.

To change the schedule (step), look here: http://munin-monitoring.org/wiki/faq#Q:CanImakeagraphshowvaluesperminuteinsteadofpersecond

Example:

 [server.example.com] address 10.0.0.1 postfix_mailstats.graph_period second 

to set the graph period in seconds. But make sure you change /etc/cron.d/munin to the minimum time interval, such as graph_period, in the file / etc / munin / munin.conf