You’re probably aware all the CVMs and hypervisor hosts in a cluster need to have IPs in the same subnet, but what about the IPMI? What are the requirements, and what’s involved in changing the IP?
The requirements are actually quite flexible. The IPMI does not have to be in the same subnet as the hosts and CVMs. You’ll see an alert and a cluster health warning if you don’t restart the genesis service on the CVMs after making changes, but the configuration can be whatever works best for your organization.
To restart the genesis service, log into the CVM via SSH or console as the user ‘nutanix’ and run the command “genesis restart”. This restart of the genesis service is non-disruptive.
Actually, you can plug the IPMI into an isolated network or configure it on a different VLAN. You could even leave it unplugged when not in use. The IPMI is very useful for installs and updates, and for troubleshooting hardware issues or an unexpected reboot but it is not required for day to day operations and doesn’t have to be reachable from the CVM.
If you want to change the IPMI networking configuration you can update it from the IPMI Web Interface, from the CLI of the hypervisor host with the ipmitool command, or if those aren’t accessible you can set it from the BIOS. All these methods are provided in the NX and SX Series Hardware Administration Guide. If you’re running a Nutanix cluster on Dell XC series, Lenovo HX series, or other OEM hardware the restrictions are the same but you’ll want to look up the docs for your specific hardware model.
In any case, like was mentioned above and in the docs please remember to restart the genesis service after making changes. The IPMI networking configuration is detected and saved during start-up and the IPMI web interface for each node is linked from the Hardware dashboard in Prism. These networking details will get refreshed by a genesis restart on the CVM.