11.2. Preparing and Adding NFS Storage

11.2.1. Preparing NFS Storage

Set up NFS shares on your file storage or remote server to serve as storage domains on Red Hat Enterprise Virtualization Host systems. After exporting the shares on the remote storage and configuring them in the Red Hat Virtualization Manager, the shares will be automatically imported on the Red Hat Virtualization hosts.

For information on setting up, configuring, mounting and exporting NFS, see Managing file systems for Red Hat Enterprise Linux 8.

Specific system user accounts and system user groups are required by Red Hat Virtualization so the Manager can store data in the storage domains represented by the exported directories. The following procedure sets the permissions for one directory. You must repeat the chown and chmod steps for all of the directories you intend to use as storage domains in Red Hat Virtualization.


  1. Install the NFS utils package.

    # dnf install nfs-utils -y
  2. To check the enabled versions:

    # cat /proc/fs/nfsd/versions
  3. Enable the following services:

    # systemctl enable nfs-server
    # systemctl enable rpcbind


  1. Create the group kvm:

    # groupadd kvm -g 36
  2. Create the user vdsm in the group kvm:

    # useradd vdsm -u 36 -g kvm
  3. Create the storage directory and modify the access rights.

    # mkdir /storage
    # chmod 0755 /storage
    # chown 36:36 /storage/
  4. Add the storage directory to /etc/exports with the relevant permissions.

    # vi /etc/exports
    # cat /etc/exports
     /storage *(rw)
  5. Restart the following services:

    # systemctl restart rpcbind
    # systemctl restart nfs-server
  6. To see which export are available for a specific IP address:

    # exportfs
     /nfs_server       <world>

If changes in /etc/exports have been made after starting the services, the exportfs -ra command can be used to reload the changes. After performing all the above stages, the exports directory should be ready and can be tested on a different host to check that it is usable.

11.2.2. Adding NFS Storage

This procedure shows you how to attach existing NFS storage to your Red Hat Virtualization environment as a data domain.

If you require an ISO or export domain, use this procedure, but select ISO or Export from the Domain Function list.


  1. In the Administration Portal, click StorageDomains.
  2. Click New Domain.
  3. Enter a Name for the storage domain.
  4. Accept the default values for the Data Center, Domain Function, Storage Type, Format, and Host lists.
  5. Enter the Export Path to be used for the storage domain. The export path should be in the format of (for IPv4), [2001:0:0:0:0:0:0:5db1]:/data (for IPv6), or domain.example.com:/data.
  6. Optionally, you can configure the advanced parameters:

    1. Click Advanced Parameters.
    2. Enter a percentage value into the Warning Low Space Indicator field. If the free space available on the storage domain is below this percentage, warning messages are displayed to the user and logged.
    3. Enter a GB value into the Critical Space Action Blocker field. If the free space available on the storage domain is below this value, error messages are displayed to the user and logged, and any new action that consumes space, even temporarily, will be blocked.
    4. Select the Wipe After Delete check box to enable the wipe after delete option. This option can be edited after the domain is created, but doing so will not change the wipe after delete property of disks that already exist.
  7. Click OK.

The new NFS data domain has a status of Locked until the disk is prepared. The data domain is then automatically attached to the data center.

11.2.3. Increasing NFS Storage

To increase the amount of NFS storage, you can either create a new storage domain and add it to an existing data center, or increase the available free space on the NFS server. For the former option, see Section 11.2.2, “Adding NFS Storage”. The following procedure explains how to increase the available free space on the existing NFS server.

Increasing an Existing NFS Storage Domain

  1. Click StorageDomains.
  2. Click the NFS storage domain’s name. This opens the details view.
  3. Click the Data Center tab and click Maintenance to place the storage domain into maintenance mode. This unmounts the existing share and makes it possible to resize the storage domain.
  4. On the NFS server, resize the storage. For Red Hat Enterprise Linux 6 systems, see Red Hat Enterprise Linux 6 Storage Administration Guide. For Red Hat Enterprise Linux 7 systems, see Red Hat Enterprise Linux 7 Storage Administration Guide.
  5. In the details view, click the Data Center tab and click Activate to mount the storage domain.