Red Hat Training

A Red Hat training course is available for Red Hat Enterprise Linux

12.4.3. Creating an LVM-based Storage Pool with virsh

This section outlines the steps required to create an LVM-based storage pool with the virsh command. It uses the example of a pool named guest_images_lvm from a single drive (/dev/sdc). This is only an example and your settings should be substituted as appropriate.

Procedure 12.3. Creating an LVM-based storage pool with virsh

  1. Define the pool name guest_images_lvm.
    # virsh pool-define-as guest_images_lvm logical - - /dev/sdc libvirt_lvm \ /dev/libvirt_lvm
    Pool guest_images_lvm defined
    
  2. Build the pool according to the specified name. If you are using an already existing volume group, skip this step.
    # virsh pool-build guest_images_lvm
    
    Pool guest_images_lvm built
    
  3. Initialize the new pool.
    # virsh pool-start guest_images_lvm
    
    Pool guest_images_lvm started
    
  4. Show the volume group information with the vgs command.
    # vgs
    VG          #PV #LV #SN Attr   VSize   VFree
    libvirt_lvm   1   0   0 wz--n- 465.76g 465.76g
    
  5. Set the pool to start automatically.
    # virsh pool-autostart guest_images_lvm
    Pool guest_images_lvm marked as autostarted
    
  6. List the available pools with the virsh command.
    # virsh pool-list --all
    Name                 State      Autostart
    -----------------------------------------
    default              active     yes
    guest_images_lvm     active     yes
    
  7. The following commands demonstrate the creation of three volumes (volume1, volume2 and volume3) within this pool.
    # virsh vol-create-as guest_images_lvm volume1 8G
    Vol volume1 created
    
    # virsh vol-create-as guest_images_lvm volume2 8G
    Vol volume2 created
    
    # virsh vol-create-as guest_images_lvm volume3 8G
    Vol volume3 created
    
  8. List the available volumes in this pool with the virsh command.
    # virsh vol-list guest_images_lvm
    Name                 Path
    -----------------------------------------
    volume1              /dev/libvirt_lvm/volume1
    volume2              /dev/libvirt_lvm/volume2
    volume3              /dev/libvirt_lvm/volume3
    
  9. The following two commands (lvscan and lvs) display further information about the newly created volumes.
    # lvscan
    ACTIVE            '/dev/libvirt_lvm/volume1' [8.00 GiB] inherit
    ACTIVE            '/dev/libvirt_lvm/volume2' [8.00 GiB] inherit
    ACTIVE            '/dev/libvirt_lvm/volume3' [8.00 GiB] inherit
    
    # lvs
    LV       VG            Attr     LSize   Pool Origin Data%  Move Log Copy%  Convert
    volume1  libvirt_lvm   -wi-a-   8.00g
    volume2  libvirt_lvm   -wi-a-   8.00g
    volume3  libvirt_lvm   -wi-a-   8.00g