Hi Steve, I'd suggest you to look at ZooKeeper-3.5.2 latest version and use dynamic reconfig feature. This will help to resize(add/remove zk server) your cluster without restarting entire cluster.
Please refer the following links to understand more about the dynamic reconfig feature:- https://zookeeper.apache.org/doc/r3.5.2-alpha/zookeeperReconfig.html http://www.slideshare.net/Hadoop_Summit/dynamic-reconfiguration-of-zookeeper Regards, Rakesh On Thu, Oct 20, 2016 at 3:19 AM, Steve Newman <[email protected]> wrote: > 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 >
