Integration overview

The XenServer-Nutanix Integration feature enables Citrix customers to reap Nutanix’s hyper-converged infrastructure (HCI) benefits such as linear scalability and reduced complexity. This feature also allows Nutanix customers to deploy XenServer on the Nutanix HCI platform. You can take advantage of the mature, fully featured, and highly optimized integration of XenServer into the wider Citrix stack. That stack includes Citrix Virtual Apps and Desktops with both MCS and PVS, and App Disks. Additionally, Nutanix customers can also benefit from the unique selling points of XenServer such as:

  • Leading graphics virtualization solution

  • Automated delivery of I/O drivers through Windows Update

  • Support for Containers

  • PVS Read Cache

  • Advanced threat detection using Direct Inspect APIs

Customers can use the Nutanix Prism web console to configure your storage and clusters (pools), and to monitor the HCI platform, including the VM storage. Managing the XenServer and performing VM lifecycle operations can be done using XenCenter.

Notes:

Compatibility requirements and caveats

With the tight integration of Nutanix with XenServer, the following XenServer features do not apply to the Nutanix HCI deployments:

  • Storage XenMotion - Storage XenMotion enables the movement of a VM’s storage from one Storage Repository (SR) to another. However, Nutanix enables the aggregation of storage for an entire cluster.

  • Disaster Recovery (DR) - The DR feature in XenServer is based on array-level mirroring that is not applicable in Nutanix deployments.

  • WLB Power Management - Within HCI environments, the removal of any hardware has to be tightly managed. This removal is orchestrated through the Nutanix Prism UI, hence the Power Management feature in XenServer Workload Balancing (WLB) is not permissible for Nutanix deployments.

  • SRs - HCIs mandate their own SR, simplifying the choice of SR type. Local, NFS, iSCSI, Hardware HBA, SMB/CIFS, and Software FCoE are not available. However, ISO libraries are supported.

  • IntelliCache - The IntelliCache feature in XenServer does not apply as Nutanix storage already ensures data locality.

  • XenCenter Automated Updates – The host-aggregated clustered storage requires that hosts are restarted in a specific sequence. When using the XenCenter Install Tools wizard, the Automated Updates option is not available. Instead choose to Download update or new version from Citrix or to Select update or supplemental pack from disk. After you have installed the updates, use the Nutanix Prism console to trigger a Rolling Pool Restart if a restart is required. This process ensures that the restarts occur in the correct sequence.

In addition, the following limitations also apply when using XenServer on Nutanix:

  • The concept of ‘cluster’ in Nutanix maps to the concept of ‘pool’ in XenServer. This mapping means that the cluster size is limited to a maximum 64 hosts per cluster.

  • High availability can only accommodate a single host failure (assuming there are at least three hosts in a cluster). This limit is only enforced in XenCenter.

  • Customers must use OVS as the network back-end. Linux Bridge is not supported.

  • The XenServer VSS provider that enables quiesced snapshots is not applicable as the integration is based on Nutanix native snapshot format.

Configuration

Use the Nutanix Prism web console to configure storage and cluster infrastructure and to monitor the HCI platform, including the VM storage. Managing the XenServer and performing VM lifecycle operations can be done using XenCenter.

Note:

Use the Nutanix Prism console to manage host membership in the cluster and pool. The options for pool-join and -eject are disabled on the XenServer user interfaces. This recommendation is because hosts in the XenServer pool must match the hosts in the Nutanix cluster.

The Nutanix software stack runs inside a privileged VM called the Controller VM (CVM) on each host. Similar to the XenServer Control Domain (dom0), the CVM domain is visible in CLI and in XenCenter on the Nutanix CVM Console tab of the host. The Controller VM is not displayed as a VM in XenCenter.

To modify the memory allocated to the Controller VM

Depending on the Nutanix features you use, you can choose to modify the memory allocated to the Controller VM. Run the following command on the Controller VM to modify the memory allocation:

xe vm-memory-limits-set uuid=<CVM UUID
static-min=10GiB dynamic-min=10GiB dynamic-max=10GiB
static-max=10GiB

Note:

Restart the host for the changes to take effect.

Integration overview