If you have problems with balance you can add new nodes using the algorithm and it'll balance out the cluster. You probably want to stick to 256 tokens though. To reduce your # tokens you'll have to do a DC migration (best way). Spin up a new DC using the algorithm on the nodes and set a lower number of tokens. You'll want to test first but if you create a new keyspace for the new DC prior to creation of the new nodes with the desired RF (ie. a keyspace just in the "new" DC with your RF) then add your nodes using that keyspace for allocation tokens *should* be distributed evenly amongst that DC, and when migrate you can decommission the old DC and hopefully end up with a balanced cluster. Definitely test beforehand though because that was just me theorising...
I'll note though that if your existing clusters don't have any major issues it's probably not worth the migration at this point. On Sat, 22 Sep 2018 at 17:40, onmstester onmstester <onmstes...@zoho.com> wrote: > I noticed that currently there is a discussion in ML with > subject: changing default token behavior for 4.0. > Any recommendation to guys like me who already have multiple clusters ( > > 30 nodes in each cluster) with random partitioner and num_tokens = 256? > I should also add some nodes to existing clusters, is it possible > with num_tokens = 256? > How could we fix this bug (reduce num_tokens in existent clusters)? > Cassandra version: 3.11.2 > > Sent using Zoho Mail <https://www.zoho.com/mail/> > > >
