If someone has upgraded SHP. Could you please clear my doubt for point 8. I have to perform this activity tomorrow. Thanks in advance !
Upgrade the search head pool
Caution: Remove each search head from the search head pool before you upgrade it, and add it back to the pool after you upgrade. While you don't need to confirm operation and functionality of each search head, only one search head at a time can be up during the upgrade phase.
1)Bring down all of the search heads in your environment. At this point, searching capability becomes unavailable, and remains unavailable until you restart all of the search heads after upgrading.
2)Place the confirmed working apps in the search head pool shared storage area.
3)Remove Search Head #1 from the search head pool.
4)Upgrade Search Head #1.
5)Restart Search Head #1.
6)Test the search head for operation and functionality. In this case, "operation and functionality" means that the instance starts and that you can log into it. It does not mean that you can use apps or objects hosted on shared storage. It also does not mean distributed searches will run correctly.
7)If the upgraded Search Head #1 functions as desired, bring it down.
8)Copy the apps and user preferences from the search head to the shared storage.
9)Add the search head back to the search head pool.
10)Restart the search head.
11) Upgrade the remaining search heads in the pool with this procedure, one by one.
This is the correct process HOWEVER, I would not continue to use the VERY BROKEN Search Head Pooling feature. There are very good reasons that it is a deprecated feature and that 99% of users have switched to the Search Head Cluster feature. I suggest that you do the same.