I am a junior technician, and I have to make an upgrede of a Vmware Vcenter Appliance 6.0 to 6.7
I have been able to see the procedure on the internet, and it seems simple, I have two doubts:
1- When this process is done, is something modified in VCSA 6.0?
2- In case of failure, would it simply work as rollback to turn off VCSA 6.7 and turn on the old VCSA 6.0?
I want to be clear in case of error how to return to the original point, it is always necessary to make a snapshot or backuo with a third party tool, but I would like some expert of the web to confirm me.
Upgrading VCSA 6.0 to VCSA 6.7 is a wizard driven process of deploying the new VCSA, doing several prechecks, and finally taking over the settings into the new VCSA.
If something goes wrong during the upgrade you can basically revert to the original VCSA by simply powering it back on (after powering off the new one). However, depending on the upgrade state you may need to add the old VCSA back to the AD. If you need to roll back after the new VCSA came up, and updated the hosts, it may be tricky to roll back. However, once it comes up, the upgrade usually succeeded.
Make sure you prepare the environment for the upgrade, i.e. ensure DNS resolution (forward, and reverse) works, the NTP serer is accessible, and you (temporarily) set DRS to "Manual" for the upgrade.
The upgrade is on a platform with the Essencial plus license.
My idea would be to migrate the VCSA 6.0 to 6.7, without touching the ESXi 6.0 for a month to see that everything is ok, and once seen that the VCSA works, update the ESXi to 6.7.
Do you see it right?
My question was whether turning on the old VCSA 6.0 would be enough to go back.
Once the new vCenter version comes up after the upgrade, it will push updates to the hosts. If you want to revert to an older vCSA at that point - or even later - you should expect some manual work to achieve this goal.
I've done lots of updates over the past years, and there has been not a single upgrade that required a rollback. So check all the requirements, and compatibility stuff (e.g. 3rd party software) before you upgrade. I usually backup the new vCSA right after the upgrade, and delete the old one right away, or one day later.