Nagios Support Forum

My company I am working for is doing a POC (proof of concept) with the Nagiosxi appliance. This appliance is running under VMware ESX 4.1. I want to configure it with more CPU so that it can handle a larger load. Is it possible to run this pre-built (configured) appliance from Nagios with more virtual processors then it is configured with from the download? Or do I have to build my own Linux server and then install the Nagios xi software on it to utilize more processors?

Thanks

- steve -

Under the ESX 4.1 you can change the number of virtual processors - "Edit Settings" -> "CPUs" (under the Hardware tab) and select the number of virtual processors from the drop-down menu.

Don't forget that vCPUs don't quite function as normal multi-core CPUs. Simply adding vCPUs will not necessarily give your VM anymore performance, and, if the ESX box has other VMs on it you will be degrading performance across the board.

General best practice for ESX is start with 1 vCPU, go to 2 vCPUs if absolutely necessary, but 80% of applications out there will not require more than 1, and 99.99% will not require more than 2 vCPUs.

There's lots out there documenting this, it's a common misconception.

To clarify: If you have 8 cores and 8 VMs, if you give each VM 1 core you will be okay, and should not have much queueing (note that the host ESX requires 1 core). If you suddenly give 1 VM 4 cores, and the other 7 VMs still have 1 core each, you now have 11 cores that could be called on at one time - thus queueing ensues, performance degrades. Make sense?

Further, if you have the Enterprise licensing (allows up to 8 vCPU per VM), you should still only go up to 7 vCPU as best practice, even if it's the only VM - because the host needs CPU to function, if you use 8 vCPUs there will be contention.

Anyways...you get the picture.

Thanks for the input chris!