Hi, when backing up metadata in Apache Druid, is it necessary to disable any Druid components, such as the master node, or is it sufficient to just stop the data deletion and ingestion processes? Additionally, is it critical if there is a segment rebalancing process between Historical nodes occurring during the metadata backup, for example?

I don't think you need to stop anything. If you want a single point in time, you could use, eg --single-transaction if it's mysqldump.