Apologies for a basic question, but I've been researching and haven't been able to find the answer online.
What is the best way to add or remove replicas from a running ZooKeeper cluster, with minimal downtime? To add a replica, the naive answer would seem to be: 1. Prepare the new replica(s), i.e. install ZooKeeper and set up the configuration files. 2. Edit the configuration for all replicas (new and existing) to list the new replicas. 3. Restart all replicas. (Simultaneously? Or gradually, one at a time?) Is this the best way to do it? Step 3 seems scary in a production cluster. Also, will the new replicas smoothly pick up the existing data, or is it better to seed them with a snapshot somehow? Similarly, the naive answer for removing a replica would seem to be: 1. Halt the ZooKeeper process. 2. Edit the configuration for all other replicas to remove the replica that's going away. 3. Restart all remaining replicas (one at a time?). Again, is this the best approach? Thanks, Steve
