How do I "apply" or "update" ISOLCPU values from terminal?

I’ve updated the ISOLCPU value with a terminal command:

ssh oneadmin@oneserver “onehost update --append 21 <<< ISOLCPUS=\"0,1,2,3\"”

And now I can see the “Isolated CPUS” on the web UI, but they are not applied to the NUMA list below. It’s waiting for me to hit the “Update” button on the web UI. But how do I perform that via the command line?

It seems like if I do run that command now that the host is up and running, the command updates the NUMA list accordingly. But it’s at setup time when I run that in the cloud-init script right after adding the host to OpenNebula that the setting doesn’t apply properly. I guess I have to add some “sleep” or something before I start updating settings to it. Sounds like a race condition.

I figured that I can’t isolate CPUs before the host comes online, as OpenNebula doesn’t know what CPUs are even available or something. So a simple while loop at setup that continues only after the host is online and then sets the ISOLCPUS seems to work.

Hi @tosaraja :wave:

Thank you very much for contributing to the Forum! I can confirm the behavior you described is exactly how OpenNebula works. First the Host needs to be monitored by OpenNebula, since OpenNebula only knows the Host’s characteristics once its status is ON.


1 Like