4 4 3 Grolar:Citrix XenServer Backup

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Docs latest icon.png Welcome to the latest SEP sesam documentation version 4.4.3 Grolar/4.4.3 Beefalo V2. For previous documentation version(s), check Citrix XenServer archive.


Overview

This article describes Citrix XenServer backup procedure. For detailed information about Citrix XenServer requirements and configuration steps, see Citrix XenServer Requirements and Configuration.

SEP sesam provides efficient data protection for virtual machines (VMs) running on a Citrix XenServer. Virtual machine-consistent backup requests a snapshot of the VM. After creation, the snapshot is exported to a SEP sesam backup medium. VSS writers on Windows VMs are notified before snapshot creation, so all VSS-aware applications, such as MS SQL, are brought into a consistent state. Note that VSS and quiesced snapshots of Windows VMs are only supported in Citrix Hypervisor 8.0 and earlier versions; they have been removed in Citrix Hypervisor ≥ 8.1 and in the version ≥ 9.0.x.x drivers. If you want to continue using the quiesced snapshot feature with Windows VMs hosted on Citrix Hypervisor 8.0 and earlier, retain your current 8.2.x.x version of the Windows I/O drivers and do not update to the 9.0.x.x drivers. For more information, see Citrix Hypervisor 8.1 Deprecations and removals.

As of version 4.4.3 Grolar, SEP sesam introduces changed block tracking (CBT) support for Citrix XenServer 7.3 and higher. The XenServer changed block tracking feature offers incremental backup capabilities thus enabling you to backup VM’s faster while saving your storage space. XenServer backup with CBT is significantly faster than regular backup without CBT and the amount of I/O required to process is reduced; with CBT, only those blocks that have changed since the previous backup are backed up. Note that Citrix XenServer CBT is available only for XenServer Enterprise Edition. For details, see Changed Block Tracking (CBT).

For the list of supported Citrix XenServer versions, see support matrix.

SEP Tip.png Tip
If you prefer to watch a video rather than to read a step-by-step guide, you can learn all the steps of the backup procedure by watching Backup of Citrix Hypervisor (XCP-ng/XenServer) with SEP sesam on SEP sesam YouTube channel.

Backup levels

In addition to previously existing COPY backup level, backup levels FULL, INC and DIFF are introduced for Citrix XenServer backup with CBT as of SEP sesam version 4.4.3 Grolar.

  • COPY: Back up the entire VM; note that a COPY backup cannot be used as a starting point for INC/DIFF backups and restores.
  • FULL: Back up the entire VM.

When performing a full backup, SEP sesam uses CBT to allow differential and incremental backups. If you use Citrix XenServer lower than 7.3 or the server is not licensed for CBT, then only COPY backups are possible.

  • INC: Back up VM data that has changed since the most recent backup.
  • DIFF: Back up VM data that has changed since the most recent full backup.
Information sign.png Note
When backing up via hypervisor and using external disk, SEP sesam cannot back up the data on the RDM disks or on a VM without the attached SCSI controller(s). The data of such disks is silently skipped from backup, hence the backup saveset contains no data for the external disk, while the backup succeeds and no warning about the missing data is issued. If a restore of a VM with external disk is performed to the original VM by using the option overwrite, the disk is re-created and all existing data on the restore target is lost.

To back these hypervisors, you have to add one or more SCSI controller to the virtual machine before performing a backup, even if there are no devices to use the SCSI, or you have to install a SEP sesam Client in the virtual machine and perform an additional file or application backup to back up this data.

Backing up the VMs and Xen templates

Create a new backup task for the Citrix Xen client containing the virtual machines. When backing up a Citrix XenServer, you can perform a hot (online) or cold (offline) backup of one VM per task. For details about backup configuration, see Standard Backup Procedure.

  1. From Main Selection -> Tasks -> By Clients, select Citrix client and click New Backup Task. The New Backup Task window opens.
  2. Specify the Source. Click the Browse button (big arrow) and select the VM you want to back up. By selecting the source, the task type and task name are set automatically.
  3. Information sign.png Note
    Citrix XenServer allows you to have more virtual machines with the same name, however, if you select one of these as a backup source, backup fails. The following error appears: Backup failed. A virtual machine with the same name already exists.

    Citrix source Beefalo V2.jpg
    You can also get the name from Xen center or on the XenServer by executing command:

     xe vm-list
    
    Information sign.png Note
    You can only configure one VM per backup task.
  4. The following additional options pre/post backup and restore commands, set encryption or compress data are not functional for the task type Citrix XenServer. However, if you want to specify OS credentials, consolidate individual tasks under a specific task group or assign a task to the schedule, click the corresponding tabs in the New Backup Task window.
  5. Citrix bck task Beefalo V2.jpg

  6. Click OK to create the task.
  7. If you want to start the newly created task immediately, right-click the name of the task and click Immediate Start. If you want to schedule the task, click New schedule under Main Selection -> Scheduling -> Schedules. For more details, see Creating a Schedule.
  8. SEP Tip.png Tip
    You can also add your backup task to an existing schedule by double-clicking the backup task, selecting the tab Schedules and adding it to one or more schedules.
  9. Once you have configured a schedule, you must create a new backup event for it. Go to Main Selection -> Scheduling -> New Backup Event, click the Parameter tab and select FULL, INC or DIFF backup from the Backup level drop-down list. For detailed procedure, see Creating a Backup Event.

The backup is done online. If XenServer tools are installed on VM, VSS-Writers are executed before making the snapshot.

Metadata backup

Backup includes the XenServer pool database and the needed metadata of the pool.

Create a new backup task for the Xen master.

  1. From Main Selection -> Tasks -> By Clients, select Citrix client and click New Backup Task. The New Backup Task window opens.
  2. Specify the Source. Use the Browse button (big arrow) and select meta-data. By selecting the source, the task type and task name are set automatically.
  3. Citrix meta data bck Beefalo V2.jpg

  4. If you want to add a comment, enter it in the Notes field.
    Click OK to create the task.
Information sign.png Note
Citrix recommends to run the metadata backup via the Citrix native backup options as often as necessary.

Host data backup

This is a file backup of the Xen hypervisor without the VMs. This is required in special cases for Citrix support. You cannot recover this host backup directly via SEP sesam back to the hypervisor.

Create a new backup task for each Xen host.

  1. From Main Selection -> Tasks -> By Clients, select Citrix client and click New Backup Task. The New Backup Task window opens.
  2. Specify the Source. Use the Browse button (big arrow) and select host-backup. By selecting the source, the task type and task name are set automatically.
  3. Citrix host bck Beefalo V2.jpg

  4. If you want to add a comment, enter it in the Notes field.
    Click OK to create the task.

Monitoring backups

You can view the status of your backup jobs by selecting Last Backup State in the Main Selection window. The backup status overview provides detailed information on the last run of backup jobs, including the task name, start and stop time of the last backup, backup level, data size, throughput, assigned media pool, etc.

Information sign.png Note
As of 4.4.3 Beefalo V2, you can check the details of your backups online by using new Web UI. For details, see SEP sesam Web UI.

Known issues

If you have problems with Citrix XenServer, check the Troubleshooting Guide.

See also

Citrix XenServer Requirements and ConfigurationCitrix XenServer RestoreChanged Block Tracking (CBT)