I have been asked a few times what is actually included in the Nutanix Operating System (NOS) PreUpgrade check available before you conduct a NOS upgrade so i figure i write a short blog post about it.
The NOS PreUpgrade check is available via the Upgrade Software link under the gear icon at the right hand side of PRISM. You can run the check manually or it will be automatically taken care of before the Upgrade process starts.
The PreUpgrade will run a set of tests to verify that your cluster is in a good state before continue with the manual or automatic upgrade. The following list includes the most important tests included in the PreUpgrade check:
- All CVMs are reachable
- Cluster state
- Cluster services
- Enough free space exists
- Metadata json release is valid and not corrupt.
- Upgrade is compatible with current version of NOS
- Upgrade software is not corrupt
There is also and PostUpgrade check running when the NOS upgrade is complete but that is not a process you can start manually via PRISM.