Build LVM From Scratch
Hope you had a great weekend. Let's get our heads back in the game with a hands-on challenge that's a cornerstone of the RHCSA exam.
This is a "Mission & a Map" post, and our mission is to master the LVM creation workflow from start to finish.
The Mission
Your mission is to take a brand new, unformatted disk and make it available to the system as a usable, mounted filesystem. This tests your knowledge of partitioning, physical volumes, volume groups, logical volumes, filesystems, and persistent mounting.
️ The Map:
The best resources are the `man` pages for the commands you'll need. This is all you get in the exam!
man fdisk (or gdisk)man pvcreate & man vgcreateman lvcreateman mkfs.xfsman fstab
Your Exam Challenge:
A new 10GB disk, /dev/vdb, has been added to your system. Your task is to perform the following steps. Post the commands for each step!
- Partition the Disk: Create one new primary partition on
/dev/vdb that uses all available space. Set the partition type to "Linux LVM".
- Create LVM Structure:
- Create a Physical Volume on the new partition (
/dev/vdb1).
- Create a new Volume Group named
vg_web using this Physical Volume.
- Create a new 4GB Logical Volume named
lv_html from the vg_web group.
- Create Filesystem: Format the new logical volume (
/dev/vg_web/lv_html) with the XFS filesystem.
- Mount Persistently:
- Create the directory
/var/www/html.
- Add an entry to
/etc/fstab to mount the new XFS volume on /var/www/html using its UUID.
- Mount the filesystem without rebooting.
- Bonus Question: What two commands would you run to extend the
lv_html volume to use 100% of the remaining free space in the vg_web group (and grow the filesystem)?
Let's see those command sequences!
