I just upgraded my indexer from 6.3.3. to 7.3.3.
The server seems to be up (as in i can log in), but it does show up as "unreachable" in de cluster overview next to another indexer which hasn't been updated.
Before the update, nothing was wrong.
Why could this happen?
The only error that i see appear is "ERROR AdminManager - Argument "generation_id" is not supported by this handler." which comes form the master environment, and showed up after upgrading the indexer. So this might be related.
Could this be to the fact that the master environment is still on version 6.3.3?
The cluster master is supposed to be upgraded before the indexers are upgraded. Also, all indexers should be upgraded at the same time. See https://docs.splunk.com/Documentation/Splunk/8.0.0/Indexer/Upgradeacluster#Upgrade_a_6.x_or_higher_i...
Hi Jeffrey. There's a very specific procedure for this. The master is the first one that needs to be upgraded, followed by the search head(s) and ALL search peers. The ink below gives you all the steps specifically for upgrading from 6.x and higher: