I’m currently upgrading the cluster to the new version (also rebooting the node to upgrade the kernel etc) and adding a new ssd to the config. The cluster is made of 7 nodes, 400GB data on each node. Replication factor is 2.
It takes 1 hour to as to start, which is not an issue, but it takes roughly 16 hours for migrations to finish with migrations threads increased to 20 and more.
My question is do I need to wait that all migrations are done or is enough to wait that the as starts and then proceed with the next node without compromising data? The extra cpu load on server is not an issue.