cPanel/WHM running slow - Install Munin

[roger]

I recently received help from Hostican support because FTP was denying logins and WHM + cPanel was VERY painfully slow.

When CPU load and memory usage are too high this happens. (That a common sense deduction!)

We tracked it down to a cron job and removed the cron job, which alleviated the issue. (The cron job could not complete, probably because some files were not available so it hogged valuable memory and CPU usage). It seems FTP logins were denied because the load was too high to authenticate in a timely manner - so logins simply failed.

Memory usage was in the burstable 1GB zone! Here's what support wrote:

"You're bursting already into that 1GB, but thats not guaranteed memory. So for example if the server doesn't have that memory available (the hardware node) you wont be able to burst into it thus your VPS will slow down.

Burstable memory means that if the memory is available it can be used, if not, then it... it tries to get as much
as it can."

One tool that can help monitor our servers and help us decide when we need to get another server, etc. is munin. From the Munin web site:

"Using Munin you can easily monitor the performance of your computers, networks, SANs, applications, weather measurements and whatever comes to mind. It makes it easy to determine "what's different today" when a performance problem crops up. It makes it easy to see how you're doing capacity-wise on any resources."

Munin is easy to install. Just log into your VPS and navigate to:

main >> cpanel >> plugins

Select (turn on) the Munin checkbox and click save at the bottom. The server will take some tome to finish installing this package so do not interrupt it.

Want to learn exactly what Munin does? Visit their web site here: http://munin.projects.linpro.no/

I hope someone finds this post helpful.
Cheers!

[lnxcode]

Yes, this is a very good module to use, it will help you filter to help. We will see about getting that into the system as default to help out.

[Librarian]

WOW, thanks Roger. I've never seen this mentioned before but it seems really useful. Thanks for the suggestion!

[Scott]

I've learned a lot by visiting this forum. Munin was new to me as well. Haha