search

LINBIT / linstor-server

High Performance Software-Defined Block Storage for container, cloud and virtualisation. Fully integrated with Docker, Kubernetes, Openstack, Proxmox etc.
https://docs.linbit.com/docs/linstor-guide/
GNU General Public License v3.0
988 stars 76 forks source link

Document downgrade process #304

Closed zamazan4ik closed 2 years ago

zamazan4ik commented 2 years ago

Hi.

After reading the documentation it is not clear for me, how downgrade process should be performed over the solution. Could you please describe somewhere in the documentation:

Thanks in advance!

ghernadi commented 2 years ago

Short answer: Linstor does not have a downgrade path.

Longer answer: The main problem is the database. If it changed, I would highly discourage from downgrading. Even if during a migration usually database columns or tables are added (which can be ignored after a downgrade), in some migrations we had to change values of existing entries. When such changes are ignored / not reverted, things could go very wrong.

If you are interested in when Linstor's DB changed, take a look at https://github.com/LINBIT/linstor-server/tree/master/controller/src/main/java/com/linbit/linstor/dbcp/migration for SQL migrations and the corresponding sub-packages for ETCD / K8s.