11.8. Storage Tasks

11.8.1. Uploading Images to a Data Storage Domain

You can upload virtual disk images and ISO images to your data storage domain in the Administration Portal or with the REST API.

Note

To upload images with the REST API, see IMAGETRANSFERS and IMAGETRANSFER in the REST API Guide.

QEMU-compatible virtual disks can be attached to virtual machines. Virtual disk types must be either QCOW2 or raw. Disks created from a QCOW2 virtual disk cannot be shareable, and the QCOW2 virtual disk file must not have a backing file.

ISO images can be attached to virtual machines as CDROMs or used to boot virtual machines.

Prerequisites

The upload function uses HTML 5 APIs, which requires your environment to have the following:

  • Image I/O Proxy (ovirt-imageio-proxy), configured with engine-setup. See Configuring the Red Hat Virtualization Manager for details.
  • Certificate authority, imported into the web browser used to access the Administration Portal.

    To import the certificate authority, browse to https://engine_address/ovirt-engine/services/pki-resource?resource=ca-certificate&format=X509-PEM-CA and enable all the trust settings. Refer to the instructions to install the certificate authority in Firefox, Internet Explorer, or Google Chrome.

  • Browser that supports HTML 5, such as Firefox 35, Internet Explorer 10, Chrome 13, or later.

Uploading an Image to a Data Storage Domain

  1. Click StorageDisks.
  2. Select Start from the Upload menu.
  3. Click Choose File and select the image to upload.
  4. Fill in the Disk Options fields. See Section 13.6.2, “Explanation of settings in the New Virtual Disk window” for descriptions of the relevant fields.
  5. Click OK.

    A progress bar indicates the status of the upload. You can pause, cancel, or resume uploads from the Upload menu.

Increasing the Upload Timeout Value

  1. If the upload times out and you see the message, Reason: timeout due to transfer inactivity, increase the timeout value:

    # engine-config -s TransferImageClientInactivityTimeoutInSeconds=6000
  2. Restart the ovirt-engine service:

    # systemctl restart ovirt-engine

11.8.2. Uploading images to an ISO domain

Note

The ISO domain is a deprecated storage domain type. The ISO Uploader tool, ovirt-iso-uploader, is removed in Red Hat Virtualization 4.4. You should upload ISO images to the data domain with the Administration Portal or with the REST API. See Section 11.8.1, “Uploading Images to a Data Storage Domain” for details.

Although the ISO domain is deprecated, this information is provided in case you must use an ISO domain.

To upload an ISO image to an ISO storage domain in order to make it available from within the Manager, follow these steps.

Procedure

  1. Login as root to the host that belongs to the Data Center where your ISO storage domain resides.
  2. Get a directory tree of /rhv/data-center:

    # tree /rhev/data-center
    .
    |-- 80dfacc7-52dd-4d75-ab82-4f9b8423dc8b
    |   |-- 76d1ecba-b61d-45a4-8eb5-89ab710a6275 → /rhev/data-center/mnt/10.10.10.10:_rhevnfssd/76d1ecba-b61d-45a4-8eb5-89ab710a6275
    |   |-- b835cd1c-111c-468d-ba70-fec5346af227 → /rhev/data-center/mnt/10.10.10.10:_rhevisosd/b835cd1c-111c-468d-ba70-fec5346af227
    |   |-- mastersd → 76d1ecba-b61d-45a4-8eb5-89ab710a6275
    |   |-- tasks → mastersd/master/tasks
    |   `-- vms → mastersd/master/vms
    |-- hsm-tasks
    `-- mnt
        |-- 10.10.10.10:_rhevisosd
        |   |-- b835cd1c-111c-468d-ba70-fec5346af227
        |   |   |-- dom_md
        |   |   |   |-- ids
        |   |   |   |-- inbox
        |   |   |   |-- leases
        |   |   |   |-- metadata
        |   |   |   `-- outbox
        |   |   `-- images
        |   |       `-- 11111111-1111-1111-1111-111111111111
        |   `-- lost+found [error opening dir]
    
    (output trimmed)
  3. Securely copy the image from the source location into the full path of 11111111-1111-1111-1111-111111111111:

    # scp root@isosource:/isos/example.iso /rhev/data-center/mnt/10.96.4.50:_rhevisosd/b835cd1c-111c-468d-ba70-fec5346af227/images/11111111-1111-1111-1111-111111111111
  4. File permissions for the newly copied ISO image should be 36:36 (vdsm:kvm). If they are not, change user and group ownership of the ISO file to 36:36 (vdsm’s user and group):

    # cd /rhev/data-center/mnt/10.96.4.50:_rhevisosd/b835cd1c-111c-468d-ba70-fec5346af227/images/11111111-1111-1111-1111-111111111111
    # chown 36.36 example.iso

The ISO image should now be available in the ISO domain in the data center.

11.8.3. Moving Storage Domains to Maintenance Mode

A storage domain must be in maintenance mode before it can be detached and removed. This is required to redesignate another data domain as the master data domain.

Important

You cannot move a storage domain into maintenance mode if a virtual machine has a lease on the storage domain. The virtual machine needs to be shut down, or the lease needs to be to removed or moved to a different storage domain first. See the Virtual Machine Management Guide for information about virtual machine leases.

Expanding iSCSI domains by adding more LUNs can only be done when the domain is active.

Moving storage domains to maintenance mode

  1. Shut down all the virtual machines running on the storage domain.
  2. Click StorageDomains.
  3. Click the storage domain’s name. This opens the details view.
  4. Click the Data Center tab.
  5. Click Maintenance.

    Note

    The Ignore OVF update failure check box allows the storage domain to go into maintenance mode even if the OVF update fails.

  6. Click OK.

The storage domain is deactivated and has an Inactive status in the results list. You can now edit, detach, remove, or reactivate the inactive storage domains from the data center.

Note

You can also activate, detach, and place domains into maintenance mode using the Storage tab in the details view of the data center it is associated with.

11.8.4. Editing Storage Domains

You can edit storage domain parameters through the Administration Portal. Depending on the state of the storage domain, either active or inactive, different fields are available for editing. Fields such as Data Center, Domain Function, Storage Type, and Format cannot be changed.

  • Active: When the storage domain is in an active state, the Name, Description, Comment, Warning Low Space Indicator (%), Critical Space Action Blocker (GB), Wipe After Delete, and Discard After Delete fields can be edited. The Name field can only be edited while the storage domain is active. All other fields can also be edited while the storage domain is inactive.
  • Inactive: When the storage domain is in maintenance mode or unattached, thus in an inactive state, you can edit all fields except Name, Data Center, Domain Function, Storage Type, and Format. The storage domain must be inactive to edit storage connections, mount options, and other advanced parameters. This is only supported for NFS, POSIX, and Local storage types.
Note

iSCSI storage connections cannot be edited via the Administration Portal, but can be edited via the REST API. See Updating Storage Connections in the REST API Guide.

Editing an Active Storage Domain

  1. Click StorageDomains and select a storage domain.
  2. Click Manage Domain.
  3. Edit the available fields as required.
  4. Click OK.

Editing an Inactive Storage Domain

  1. Click StorageDomains.
  2. If the storage domain is active, move it to maintenance mode:

    1. Click the storage domain’s name. This opens the details view.
    2. Click the Data Center tab.
    3. Click Maintenance.
    4. Click OK.
  3. Click Manage Domain.
  4. Edit the storage path and other details as required. The new connection details must be of the same storage type as the original connection.
  5. Click OK.
  6. Activate the storage domain:

    1. Click the storage domain’s name. This opens the details view.
    2. Click the Data Center tab.
    3. Click Activate.

11.8.5. Updating OVFs

By default, OVFs are updated every 60 minutes. However, if you have imported an important virtual machine or made a critical update, you can update OVFs manually.

Updating OVFs

  1. Click StorageDomains.
  2. Select the storage domain and click More Actions ( moreactions ), then click Update OVFs.

    The OVFs are updated and a message appears in Events.

11.8.6. Activating Storage Domains from Maintenance Mode

If you have been making changes to a data center’s storage, you have to put storage domains into maintenance mode. Activate a storage domain to resume using it.

  1. Click StorageDomains.
  2. Click an inactive storage domain’s name. This opens the details view.
  3. Click the Data Centers tab.
  4. Click Activate.
Important

If you attempt to activate the ISO domain before activating the data domain, an error message displays and the domain is not activated.

11.8.7. Detaching a Storage Domain from a Data Center

Detach a storage domain from one data center to migrate it to another data center.

Detaching a Storage Domain from the Data Center

  1. Click StorageDomains.
  2. Click the storage domain’s name. This opens the details view.
  3. Click the Data Center tab.
  4. Click Maintenance.
  5. Click OK to initiate maintenance mode.
  6. Click Detach.
  7. Click OK to detach the storage domain.

The storage domain has been detached from the data center, ready to be attached to another data center.

11.8.8. Attaching a Storage Domain to a Data Center

Attach a storage domain to a data center.

Attaching a Storage Domain to a Data Center

  1. Click StorageDomains.
  2. Click the storage domain’s name. This opens the details view.
  3. Click the Data Center tab.
  4. Click Attach.
  5. Select the appropriate data center.
  6. Click OK.

The storage domain is attached to the data center and is automatically activated.

11.8.9. Removing a Storage Domain

You have a storage domain in your data center that you want to remove from the virtualized environment.

Procedure

  1. Click StorageDomains.
  2. Move the storage domain to maintenance mode and detach it:

    1. Click the storage domain’s name. This opens the details view.
    2. Click the Data Center tab.
    3. Click Maintenance, then click OK.
    4. Click Detach, then click OK.
  3. Click Remove.
  4. Optionally select the Format Domain, i.e. Storage Content will be lost! check box to erase the content of the domain.
  5. Click OK.

The storage domain is permanently removed from the environment.

11.8.10. Destroying a Storage Domain

A storage domain encountering errors may not be able to be removed through the normal procedure. Destroying a storage domain forcibly removes the storage domain from the virtualized environment.

Destroying a Storage Domain

  1. Click StorageDomains.
  2. Select the storage domain and click More Actions ( moreactions ), then click Destroy.
  3. Select the Approve operation check box.
  4. Click OK.

11.8.11. Creating a Disk Profile

Disk profiles define the maximum level of throughput and the maximum level of input and output operations for a virtual disk in a storage domain. Disk profiles are created based on storage profiles defined under data centers, and must be manually assigned to individual virtual disks for the profile to take effect.

This procedure assumes you have already defined one or more storage quality of service entries under the data center to which the storage domain belongs.

Creating a Disk Profile

  1. Click StorageDomains.
  2. Click the data storage domain’s name. This opens the details view.
  3. Click the Disk Profiles tab.
  4. Click New.
  5. Enter a Name and a Description for the disk profile.
  6. Select the quality of service to apply to the disk profile from the QoS list.
  7. Click OK.

11.8.12. Removing a Disk Profile

Remove an existing disk profile from your Red Hat Virtualization environment.

Removing a Disk Profile

  1. Click StorageDomains.
  2. Click the data storage domain’s name. This opens the details view.
  3. Click the Disk Profiles tab.
  4. Select the disk profile to remove.
  5. Click Remove.
  6. Click OK.

If the disk profile was assigned to any virtual disks, the disk profile is removed from those virtual disks.

11.8.13. Viewing the Health Status of a Storage Domain

Storage domains have an external health status in addition to their regular Status. The external health status is reported by plug-ins or external systems, or set by an administrator, and appears to the left of the storage domain’s Name as one of the following icons:

  • OK: No icon
  • Info: Info
  • Warning: Warning
  • Error: Error
  • Failure: Failure

To view further details about the storage domain’s health status, click the storage domain’s name. This opens the details view, and click the Events tab.

The storage domain’s health status can also be viewed using the REST API. A GET request on a storage domain will include the external_status element, which contains the health status.

You can set a storage domain’s health status in the REST API via the events collection. For more information, see Adding Events in the REST API Guide.

11.8.14. Setting Discard After Delete for a Storage Domain

When the Discard After Delete check box is selected, a blkdiscard command is called on a logical volume when it is removed and the underlying storage is notified that the blocks are free. The storage array can use the freed space and allocate it when requested. Discard After Delete only works on block storage. The flag is not available on the Red Hat Virtualization Manager for file storage, for example NFS.

Restrictions:

  • Discard After Delete is only available on block storage domains, such as iSCSI or Fibre Channel.
  • The underlying storage must support Discard.

Discard After Delete can be enabled both when creating a block storage domain or when editing a block storage domain. See Preparing and Adding Block Storage and Editing Storage Domains.

11.8.15. Enabling 4K support on environments with more than 250 hosts

By default, GlusterFS domains and local storage domains support 4K block size on Red Hat Virtualization environments with up to 250 hosts. 4K block size can provide better performance, especially when using large files, and it is also necessary when you use tools that require 4K compatibility, such as VDO.

The lockspace area that Sanlock allocates is 1 MB when the maximum number of hosts is the default 250. When you increase the maximum number of hosts when using 4K storage, the lockspace area is larger. For example, when using 2000 hosts, the lockspace area could be as large as 8 MB.

You can enable 4K block support on environments with more than 250 hosts by setting the engine configuration parameter MaxNumberOfHostsInStoragePool.

Procedure

  1. On the Manager machine enable the required maximum number of hosts:

    # engine-config -s MaxNumberOfHostsInStoragePool=NUMBER_OF_HOSTS
  2. Restart the JBoss Application Server:

    # service jboss-as restart

For example, if you have a cluster with 300 hosts, enter:

# engine-config -s MaxNumberOfHostsInStoragePool=300
# service jboss-as restart

Verification

View the value of the MaxNumberOfHostsInStoragePool parameter on the Manager:

 # engine-config --get=MaxNumberOfHostsInStoragePool
 MaxNumberOfHostsInStoragePool: 250 version: general

11.8.16. Disabling 4K support

By default, GlusterFS domains and local storage domains support 4K block size. 4K block size can provide better performance, especially when using large files, and it is also necessary when you use tools that require 4K compatibility, such as VDO.

You can disable 4K block support.

Procedure

  1. Ensure that 4K block support is enabled.

    $ vdsm-client Host getCapabilities
    …​
    {
        "GLUSTERFS" : [
             0,
             512,
             4096,
        ]
        …​
  2. Edit /etc/vdsm/vdsm.conf.d/gluster.conf and set enable_4k_storage to false. For example:

    $ vi  /etc/vdsm/vdsm.conf.d/gluster.conf
    
    [gluster]
    # Use to disable 4k support
    # if needed.
    enable_4k_storage = false