2023-02-11 Major upgrade postgresql
On my todo-list was a postgresql upgrade from 9.6 to 11, a lingering item from the earlier devuan upgrades from ascii to beowulf. This is one of those upgrades where I am very happy to have lvm snapshots so I know I can get back to a working state if something really goes wrong. With that snapshot and the instructions from From Stretch to Buster : How to upgrade a 9.6 PostgreSQL cluster to 11 ? - Samuel Forestier it all went fine. After the upgrade I tested all my database-driven websites and local tools to see if they worked. All worked fine so I could stop and delete the 9.6 main postgres cluster and continue running 11. Final cleanup was deleting the snapshot. Which used as much space as the size of the database! Not unsurprising when thinking about how the upgrade works, but think about the snapshot size.