As long as the number of racks is already at/above the number of nodes / replication factor, it's gonna be fine.
Where it tends to surprise people is if you have RF=3 and either 1 or 2 racks, and then you add a third, that third rack gets one copy of "all" of the data, so you often run out of disk space. If you're already at 3 nodes / 3 racks / RF=3, you're already evenly distributed, the next (4th, 5th, 6th) racks will just be randomly assigned based on the random token allocation. On Mon, Apr 3, 2023 at 8:12 AM David Tinker <david.tin...@gmail.com> wrote: > I have a 3 node cluster using the GossipingPropertyFileSnitch and > replication factor of 3. All nodes are leased hardware and more or less the > same. The cassandra-rackdc.properties files look like this: > > dc=dc1 > rack=rack1 > (rack2 and rack3 for the other nodes) > > Now I need to expand the cluster. I was going to use rack4 for the next > node, then rack5 and rack6 because the nodes are physically all on > different racks. Elsewhere on this list someone mentioned that I should use > rack1, rack2 and rack3 again. > > Why is that? > > Thanks > David > >
