Chapter 10. Configure Red Hat Gluster Storage for Hosted Engine using the Web Console

Important

Ensure that disks specified as part of this deployment process do not have any partitions or labels.

  1. Log into the Web Console

    Browse to the Web Console management interface of the first hyperconverged host, for example, https://node1.example.com:9090/, and log in with the credentials you created in Section 5.1, “Installing hyperconverged hosts”.

  2. Start the deployment wizard

    1. Click Virtualization → Hosted Engine and click Start underneath Hyperconverged.

      Hosted Engine Setup screen with Start buttons underneath the Hosted Engine and Hyperconverged options

      The Gluster Configuration window opens.

    2. Click the Run Gluster Wizard button.

      Selecting the type of hyperconverged deployment in the Web Console

      The Gluster Deployment window opens in 3 node mode.

  3. Specify hosts

    1. If your hosts do not use multiple networks, check the Use same hostname for storage and public network checkbox.
    2. If your hosts use IPv6 networking, check the Select if hosts are using IPv6 checkbox. Your hosts must use FQDNs if you select this option; IPv6 addresses are not supported.

    3. Specify the back-end (storage network) and front-end (public network) FQDNs of the hyperconverged hosts.

      In the Host1 field, specify the FQDN of the hyperconverged host that can SSH to other hosts without a password using key-based authentication.

      The Hosts tab of the Gluster Deployment window with example IP addresses in the Host Address fields
    4. Click Next.

  4. Specify volumes

    Specify the volumes to create.

    The Volumes tab of the Gluster Deployment window with the default values shown
    Name
    Specify the name of the volume to be created.
    Volume Type
    Only replicated volumes are supported for three-node deployments.
    Arbiter
    Specify whether to create the volume with an arbiter brick. If this box is checked, the third disk stores only metadata.
    Brick Dirs
    The directory that contains this volume’s bricks. Use a brick path of the format gluster_bricks/<volname>/<volname>.

    The default values are correct for most installations.

    If you need more volumes, click Add Volumes to add another row and enter your extra volume details.

  5. Specify bricks

    Enter details of the bricks to be created.

    The Bricks tab of the Gluster Deployment window with the default values shown
    RAID Type
    Specify the RAID configuration of the host. Supported values are raid5, raid6, and jbod. Setting this option ensures that your storage is correctly tuned for your RAID configuration.
    Stripe Size
    Specify the RAID stripe size in KB. This can be ignored for jbod configurations.
    Data Disk Count
    Specify the number of data disks in your host’s RAID volume. This can be ignored for jbod configurations.
    Blacklist Gluster Devices
    Prevents the disk that is specified as a Gluster brick from using a multipath device name. If you want to use a multipath device name, uncheck this checkbox and use the /dev/mapper/<WWID> format to specify your device in the Device field.
    Select Host
    If your hosts should use different device names or sizes, use this drop-down menu to change to the host you want to configure.
    LV Name
    The name of the logical volume to be created. This is pre-filled with the name that you specified on the previous page of the wizard.
    Device Name
    Specify the raw device you want to use in the format /dev/sdc. Use /dev/mapper/<WWID> format for multipath devices. Use /dev/mapper/luks_<name> format for devices using Network-Bound Disk Encryption.
    LV Size
    Specify the size of the logical volume to create in GiB. Do not enter units, only the number. This number should be the same for all bricks in a replicated set. Arbiter bricks can be smaller than other bricks in their replication set.
    Recommendation for LV size
    Logical volume for engine brick must be a thick LV of size 100GB, other bricks created as thin LV reserving 16GB for thinpool metadata and 16GB reserved for spare metadata.

    Example: 

If the host has a disk of size 1TB, then
engine brick size = 100GB ( thick LV )
Pool metadata size = 16GB
Spare metadata size = 16GB
Available space for thinpool = 1TB - ( 100GB + 16GB + 16GB ) = 868 GB

Other bricks for volumes can be created with the available thinpool storage space of 868GB, for example, vmstore brick with 200GB and data brick with 668GB.

Enable Dedupe & Compression

Specify whether to provision the volume using VDO for compression and deduplication at deployment time. The logical size of the brick is expanded to 10 times the size of physical volume as part of VDO space savings.

Note

Ensure to enable Dedupe & Compression on all the bricks which are part of the volume.

Configure LV Cache

Optionally, check this checkbox to configure a small, fast SSD device as a logical volume cache for a larger, slower logical volume.

  • Add the device path to the SSD field.
  • Specify the Thinpool device to attach the cache device to.
  • Add the size to the LV Size (GB) field.
  • Set the Cache Mode used by the device.
Warning

To avoid data loss when using write-back mode, Red Hat recommends using two separate SSD/NVMe devices. Configuring the two devices in a RAID-1 configuration (via software or hardware), significantly reduces the potential of data loss from lost writes.

For further information about lvmcache configuration, see LVM cache logical volumes in the Red Hat Enterprise Linux 8 documentation.

  1. Review and edit configuration

    The Review tab of the Gluster Deployment window with part of the generated deployment configuration file visible

    1. Click Edit to begin editing the generated deployment configuration file.

      Make any changes required and click Save.

    2. Review the configuration file.

      If all configuration details are correct, click Deploy.

  2. Wait for deployment to complete

    You can watch the progress of the deployment in the text field.

    The window displays Successfully deployed gluster when complete.

    The final screen of the Gluster Deployment window showing a message that says Successfully deployed Gluster and a button to Continue to Hosted Engine Deployment

    Click Continue to Hosted Engine Deployment and continue the deployment process with the instructions in Chapter 11, Deploy the Hosted Engine using the Web Console.

Important

If deployment fails, click Clean up to remove any potentially incorrect changes to the system. If your deployment uses Network-Bound Disk Encryption, you must then follow the process in Cleaning up Network-Bound Disk Encryption after a failed deployment.

When cleanup is complete, click Redeploy. This returns you to the Review and edit configuration tab so that you can correct any issues in the generated configuration file before reattempting deployment.