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Hands-on Lab·LPIC-2

Building LVM on a real disk

The whole LVM stack on a genuinely spare 5 GB disk: physical volume, volume group, logical volume, filesystem, mount. Then the operation that is the reason LVM exists - extending a mounted filesystem while it stays in use - and the two-step nature of it that catches people out.

201: Filesystems and Storage Guide 6 of 29 Intermediate

One host with a real 5 GB spare disk at /dev/sdb. Everything on this page happens on that disk, which is wiped back to bare at the end.
Server NameIP AddressOSRolesCPURAMHDD
LPIC2-A01192.168.0.78Ubuntu 26.04 LTSPrimary service host - BIND, Apache, Samba, Postfix. Topic 204 RAID runs on loop devices; this machine has no spare disk2 Core4 GB50 GB

This guide includes

Use this for the whole LVM stack on a genuinely spare disk. This matters because proving the disk is safe before destroying it is the habit worth building - everything after that step is reversible, and that step is not.

Before you start

  1. Prove the disk is safe before you destroy it

  2. Physical volume, then volume group

  3. A logical volume, a filesystem, a mount

  4. Growing it while it stays mounted

Official sources