v.21.12Improvements

clickhouse-keeper prevents startups and config changes with duplicate IDs or endpoints

Now clickhouse-keeper refuses to start or apply configuration changes when they contain duplicated IDs or endpoints. Fixes #31339. #32121 (alesapin).
ClickHouse Keeper now refuses to start or apply configuration changes if the configuration contains duplicated IDs or endpoints.

Why it matters

This feature prevents configuration errors by ensuring that each ID and endpoint in ClickHouse Keeper's configuration is unique. It avoids potential conflicts and instability caused by duplicated identifiers, enhancing system reliability and simplifying troubleshooting.

How to use it

When configuring ClickHouse Keeper, ensure that all IDs and endpoints are unique. Upon detecting duplicates, ClickHouse Keeper will refuse to start or apply the configuration changes, prompting users to correct the configuration before proceeding.