Chapter 4. Hosting Virtual Machine Images on Red Hat Gluster Storage volumes

Procedure 4.1. Configuring Volumes Using the Command Line Interface

1. Configure the rhgs-random-io tuned profile

   Install the tuned tuning daemon and configure Red Hat Gluster Storage servers to use the rhgs-random-io profile:

   # yum install tuned
   # tuned-adm profile rhgs-random-io

   For more information on available tuning profiles, refer to the tuned-adm man page, or see the Red Hat Gluster Storage 3.5 Administration Guide: https://access.redhat.com/documentation/en-us/red_hat_gluster_storage/3.5/html/administration_guide/.

   Note

   When you upgrade, a new virt file may be created in /var/lib/glusterd/groups/virt.rpmnew. Apply the new virt file to the existing volumes by renaming the virt.rpmnew file to virt.

2. Assign volumes to virt group

   Assign volumes that store virtual machine images to the virt volume group to apply the settings in the virt profile. This has the same effect as the Optimize for Virt Store option in the management console.

   # gluster volume set VOLNAME group virt

   See Appendix A, The virt group profile for more information about this configuration.

   Important

   Volumes in the virt group must only be used for storing machine images, and must only be accessed using the native FUSE client.

3. (Recommended) Configure improved self-heal performance

   Run the following command to improve the performance of volume self-heal operations.

   # gluster volume heal volname cluster.granular-entry-heal enable

4. Allow KVM and VDSM brick access

   Set the brick permissions for vdsm and kvm. If you do not set the required brick permissions, creation of virtual machines fails.
   1. Set the user and group permissions using the following commands:

      # gluster volume set VOLNAME storage.owner-uid 36
      # gluster volume set VOLNAME storage.owner-gid 36

   2. If you are using QEMU/KVM as a hypervisor, set the user and group permissions using the following commands:

      # gluster volume set VOLNAME storage.owner-uid 107
      # gluster volume set VOLNAME storage.owner-gid 107