> On 26 Nov 2025, at 14:25, Sebastian Marsching <[email protected]> wrote: > > >> Is it possible to upgrade a two–data center Cassandra 4 deployment to >> Cassandra 5.0 without downtime, using a node-by-node rolling upgrade >> approach? > > Yes, this scenario is supported and, if done correctly, should not result in > any downtime. Just be aware that topology changes are not possible while > running mixed versions, so you probably want to plan to complete the update > procedure in a reasonably short amount of time.
What is meant by changing the topology? Does this refer to modifying token ranges and their assignments? What happens if one of the nodes fails during the upgrade? Will it be possible to perform recovery using -Dcassandra.replace_address?
