If you have this problem on a SH node, you can use the official Fix Raft issues on a member:
To fix a Raft issue, clean the member's _raft folder. Run the splunk clean raft command on the member:
Stop the member:
splunk stop
Clean the member's raft folder:
splunk clean raft
Start the member:
splunk start
The _raft folder will be repopulated from the captain
this is described in the documentation:
https://docs.splunk.com/Documentation/Splunk/7.1.2/DistSearch/Handleraftissues
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