Xen End of Support

OnApp 6.4 is the last version of OnApp that includes full support for the Xen compute resources. In OnApp 6.5 Xen virtualization type will not be supported. 

Until version 6.5, OnApp has supported both Xen and KVM virtualization technologies. Over the years, KVM became more mature and was adopted into the Linux Kernel and has become the default choice when deploying new OnApp Clouds.
For OnApp to be able to focus our new feature and maintenance efforts towards one open-source Hypervisor platform it means more streamlined planning, development, testing, and release cycles, and most importantly less complexity and a better experience for users.
For those reasons, OnApp has decided to move forward with a focus on KVM and announce the end of Xen support.

This page includes the current information on the end of support of Xen compute resources in OnApp 6.5, as well as recommendations related to the migration of workloads from Xen to KVM. 

Upgrade recommendations for Xen compute resources

If you have OnApp version <= 6.3 with Xen compute resources, the following upgrade options are available:

  • Stay on Xen compute resources and upgrade to OnApp 6.4 version that fully supports Xen. When Xen reaches End of Life in OnApp, we’ll provide two years of technical guidance support for Xen compute resources in OnApp 6.4 to help the customers make the transition to KVM.
  • Migrate all of your compute resources to KVM and upgrade to OnApp 6.5 with the full support of KVM.
  • Stay on Xen compute resources and upgrade to OnApp 6.5. Since 6.5 will still keep the Xen related elements in the product (although unsupported) until OnApp 7.1.

For more information on both options, refer to the sections below. 

Upgrade to 6.5 

In this version, OnApp will change the support status of Xen to End of Support, so no new Xen packages will be released. To upgrade the cloud with Xen compute resources from 6.4, it is necessary to migrate all your VSs on Xen compute resources to KVM.

If you don't have any KVM compute resources installed, refer to the Install Compute Resources guide for the installation instructions. 

To migrate your VSs from Xen to KVM, you should first add a KVM compute resource to the same zone as the Xen compute resource. Then, you may use the free Xen to KVM migration feature to easily switch to KVM virtualization. During the migration, the billing will be changed due to the increase of disk size (all disks except swap disks increase in size by 1 GB). The new estimated price per hour for a VS will be displayed at the bottom of the VS migration screen.

Xen to KVM migration is irreversible and you cannot migrate from KVM to Xen compute resources.

Migration is not performed for:

  • Integrated Storage data stores (if any of the disks has active backups running or zombie snapshots)

  • SolidFire data stores

  • Federated virtual servers in compute zones submitted to the Marketplace


  • Clone the VS before migration or enable the additional backup option in the migration wizard to prevent potential data loss.
  • Make sure that a virtual server does not have temporary disks (attached to or from another virtual server).
  • Make sure that destination compute resources are running on CentOS 7. If not, you must migrate or update your CentOS 6 compute resources first.
  • Ensure that networks attached to a VS running on Xen compute resources are attached to KVM compute resources too.
  • Make sure your target data stores have enough space and are added to the target data store zone in your bucket. 
  • If both source and destination compute resources have backup IP addresses, VS migration will be performed using those backup IP addresses as an alternative network for traffic. 

    You may use a backup network not to load the management network.

  • If you have TRIM enabled for at least one target data store before the migration, it can be enabled after the migration with the next VS reboot.

For more info and detailed migration instructions, refer to Xen to KVM migration.

After migration, you may proceed with updating your cloud to 6.5.

Upgrade to 6.4

OnApp 6.4 is the last version that provides full support of Xen. If you decide not to switch to KVM so far, you may upgrade to the latest version of 6.4. Xen packages are still released for this version, so you may take advantage of the features presented in 6.4 and migrate to KVM later.

If you have any further questions or need upgrade assistance, do not hesitate to contact support or your account manager on amteam@onapp.com.

If you need to install Xen compute resource on an existing Control Panel, refer to the Install Xen Compute Resource guide.