Increasing poller time to 1-minute

[swillett11]

Hello - I am seeking advice on how to increase poller time to 1-minute for all of my data sources. I am currently using the Default 5-min Data Source Profile. (v1.1.38 - unix)
Can I just add the 1-minute interval into the current Default 5-min profile? I also saw where I would need to config 1-minute polling in Configuration > Settings > Poller > Poller Interval.

Also, do I need to also adjust the Cron interval? I am new to Cacti, and would like to see if anyone could steer me in the right direction on this as I am reading old docs that ref crashing Cacti if this is not done correctly. Anyone else done this before, or know how to make this 1-minute polling interval change?

[netniV]

There is already a 1 minute profile (or should be) defined. I think all you have to do is make that your default profile and then update cron to run that often. This will make all new RRD/RRA's be in the 1 minute cycle. It would not change existing data sources from 5 minutes though. To do that, you'd have to start over by removing the data sources. etc.

I have never personally done that, so I'm not 100% confident that it's that simple so I would always advise spinning up a test server, running at the 5 minutes interval, then attempt the switch to 1minute.

[tertius]

You don't need to reduce the cron interval (5 minutes). Only set the Poller interval to your smallest interval you defined for a data profile (1 minute).

This way, the poller is started every 5 minutes (Cron interval) and collects data 5 times, once every minute (poller interval), then terminates. After 5 minutes (cron interval) it is started again by cron for the next 5 polls, and so on.

[Osiris]

If you have existing graphs and wish to change their profile, you should pm @browniebraun to get him to publish his script that can restructure the rrdfiles and reimport data into them, since that is what would be required.

[swillett11]

There is already a 1 minute profile (or should be) defined. I think all you have to do is make that your default profile and then update cron to run that often. This will make all new RRD/RRA's be in the 1 minute cycle. It would not change existing data sources from 5 minutes though. To do that, you'd have to start over by removing the data sources. etc.

I have never personally done that, so I'm not 100% confident that it's that simple so I would always advise spinning up a test server, running at the 5 minutes interval, then attempt the switch to 1minute.

--
Thanks NetniV

[swillett11]

If you have existing graphs and wish to change their profile, you should pm @browniebraun to get him to publish his script that can restructure the rrdfiles and reimport data into them, since that is what would be required.

--
Osiris,

Would this be the same as "rebuilding" the poller cache? Or would his script do something different?

[swillett11]

You don't need to reduce the cron interval (5 minutes). Only set the Poller interval to your smallest interval you defined for a data profile (1 minute).

This way, the poller is started every 5 minutes (Cron interval) and collects data 5 times, once every minute (poller interval), then terminates. After 5 minutes (cron interval) it is started again by cron for the next 5 polls, and so on.

--
tertius,

Thanks for responding. Have you actually performed this change on Cacti 1.1.38 before? That makes sense what you posted, but I was reading about how this can crash Cacti if not executed correctly.

[netniV]

You should be fine.

[tertius]

This will not "crash" cacti. It's a perfectly fine way to get a smaller interval. I use it since years for 30-seconds polling of some sources.

The only thing you have to do after changing this setting is repopulating the poller cache, and that is also written as a reminder in the configuration page.