Storage

Physical volumes, volume groups, and logical volumes — the abstraction layer between raw disks and filesystems.

Extending, reducing, pvmove, vgextend, lvresize — managing LVM infrastructure once it's running in production.

Creating, mounting, merging, and backup use cases — point-in-time snapshots for safe backups and rollback.

Levels, mdadm basics, and monitoring — combining multiple disks for redundancy and performance.