leaderServes=no causes rolling restart kerfuffle with automatic instance management
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Was running some ZK performance benchmarks and wanted to examine effect of the leaderServes setting; I did not realize initially that this setting also made leader refuse to respond to four letter checks (or rather respond with "This ZooKeeper instance is not currently serving requests")
This seems to cause exhibitor to consider the leader unhealthy and attempt to restart it; in doing so it changes the shared server list which in turn also restarts other nodes in ensemble.
In general, it appears that Exhibitor is basically incompatible with this setting. This should perhaps not be the case? but if it is to be the case, it probably ought to be documented (or perhaps refused if typed into the Additional Config box in the UI)
Hi @donaldguy thanks for that. Exhibitor uses four letter words to monitor the co-located zk server process, so if they do not work then exhibitor will not be able to work also. We will look into what we can do to support leaderServes=no, but as of right now it would not work.