Linux Storage Management

Question 1

How do you list the block devices?

Answer 1

lsblk

Question 2

What are the layers of lvm2, describe them?

Answer 2

Physical volumes - Actual physical storage, disks, partitions and raw files
Volume groups - Aggregates physical volumes
Logical volumes - Dev mapper devices which are formatted and presented to the consumer as a block device

Question 3

What is a dev-mapper?

Answer 3

A dev-mapper is a framework for mapping physical block devices onto virtual ones. They work by passing data from the virtual block devices onto the physical ones.

Question 4

What command allows you to create a file storage?

Answer 4

fallocate -l 500M /tmp/file1

Question 5

For each of the lvm layers what commands do you use to list, create and remove entities?

Answer 5

physical volume - pvcreate, pvremove, pvs
volume group - vgcreate, vgremove, vgs
logical volume - lvcreate, lvremove, lvs

Question 6

How to you attatch a file to a loop device to be used as block storage?

Answer 6

losetup -f /path/to/file

The -f option allocates the file to the next available loop device