Complete procedures with a way back.

Create a mirrored OpenZFS data pool from stable device identities, separate data into policy-aware datasets, recover individual files from snapshots, verify every block with scheduled scrubs, replace a failed member without confusing device names, and rehearse a read-only import path before an incident.

Build a two-member data RAID 1 array, persist assembly and mounting, monitor synchronization and consistency, rehearse a controlled member failure, and rebuild onto a positively identified replacement.

Safely add capacity to an online thick LVM logical volume, with an optional new physical volume, a tested size plan, separate ext4 and XFS growth paths, and evidence that the application received usable space.

Copy an Ubuntu root filesystem to a larger ext4 disk, preserve Linux metadata, rebuild UUID-based boot artifacts, perform a controlled cutover, and retain the original disk as a tested rollback.