Creating and Managing KVM Storage Pools Effectively

Storage pools in KVM virtualization are a way to centrally manage and organize storage resources for virtual machines. A storage pool is a designated area of storage, such as a directory, partition, or network-based storage, that is set aside for use by KVM virtual machines. Once a storage pool is created and started, storage volumes can be defined within the pool and assigned to VMs.

This allows virtual machine disk images and other files to be managed in a structured way, rather than having storage spread across the host system. Storage pools provide a level of abstraction that makes it easier to provision and manage storage for VMs. Different types of storage pools are supported, including directory-based, LVM-based, iSCSI, and NFS. Creating and managing storage pools is an important part of setting up a KVM virtualization environment.

To create a new storage pool for KVM virtual machine images, you can use the virsh command-line tool. First, define the new storage pool by specifying its name and type.

For example, to create a directory-based storage pool named “vmdisks” that uses the /vmdisks directory, run the command:

virsh pool-define-as --name vmdisks \
--type dir \
--target /vmdisks

Next, build and start the new storage pool:

virsh pool-build vmdisks
virsh pool-start vmdisks

You can also optionally configure the pool to automatically start when the libvirt service starts:

virsh pool-autostart vmdisks

Sometimes you have to refresh a pool’s information cache.

You can do it with the pool refresh command:

virsh pool-refresh --pool kvm-vms

Once the new storage pool is created and started, you can then create storage volumes within it that can be used to store virtual machine disk images and other files.

The newly created storage pool must have the proper permissions: the qemu (or libvirt-quemu on Debian) user must have read and execute access on it.

A simple ACL can solve it:

setfacl -m "user:libvirt-qemu:rx" /vmdisks

The storage pool provides a centralized and organized way to manage storage resources for your KVM virtual machines.

You can list the volumes in a pool with the vol-list option:

virsh vol-list --pool default

or

virsh vol-list --pool default --details

With these commands you can start managing your storage pools of your KVM infrastructure.

If you want to discuss the topic with other technology-minded people, join my Discord: https://discord.gg/YbSYGsQYES

Now we have an IRC channel as well: irc.libera.chat / #tomsitcafe