Hi,
Before a migration we tested a database restore on the new server -- which was configured to archive its WAL, and has archived WAL on a new timeline to our central backup server. We tested this twice.
Now we have done the migration, which due to the size of the database we achieved by detaching the disks from the old server and attaching them to the new (this was the easiest way to achieve an OS upgrade from Ubuntu 20.04 to Debian 12). ((Yes we reindexed the text columns.))
So now our new server is still on the original timeline, but our backup server contains WAL from two new timelines.
What should we do? Can we safely remove that WAL from the backup server? How?
Thanks,
Colin