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Backing up single host installations
Use the CLI to backup the pool database. To obtain a consistent pool metadata backup file, run pool-dump-
database on the XenServer host and archive the resulting file. The backup file will contain sensitive authentication
information about the pool, so ensure it is securely stored.
To restore the pool database, use the xe pool-restore-database command from a previous dump file. If your
XenServer host has died completely, then you must first do a fresh install, and then run the pool-restore-database
command against the freshly installed XenServer host.
After a restoration of the pool database, some VMs may still be registered as being Suspended, but if the
storage repository with their suspended memory state (defined in the suspend-VDI-uuid field) was a local
SR, it will no longer be available since the host has been reinstalled. To reset these VMs back to the Halted
state so that they can be started up again, use the xe vm-shutdown vm=vm_name -force command, or use the
xe vm-reset-powerstate vm=<vm_name> -force command.
Warning:
XenServer hosts restored using this method will have their UUIDs preserved. If you restore
to a different physical machine while the original XenServer host is still running, there will
be duplicate UUIDs. The main observable effect of this will be that XenCenter will refuse
to connect to the second XenServer host. Pool database backup is not the recommended
mechanism for cloning physical hosts; use the automated installation support for that (see
the XenServer Installation Guide).
Backing up pooled installations
In a pool scenario, the master host provides an authoritative database that is synchronously mirrored to all the
member hosts in the pool. This provides a degree of built-in redundancy to a pool; the master can be replaced
by any member since each of them has an accurate version of the pool database. Please refer to the XenServer
Administrator's Guide for more information on how to transition a member into becoming a master host.
This level of protection may not be sufficient; for example, if your shared storage containing the VM data is backed
up in multiple sites, but your local server storage (containing the pool metadata) is not. To fully recreate a pool
given just a set of shared storage, you must first backup the pool-dump-database file on the master host, and
archive this file.
Subsequently restoring this backup on a brand new set of hosts
1. Install a fresh set of XenServer hosts from the installation media, or over PXE.
2. Use the xe pool-restore-database on the host designated to be the new master.
3. Run the xe host-forget command on the new master to remove the old member machines.
4. Use the xe pool-join command on the member hosts to connect them to the new pool.
Backing up XenServer hosts
This section describes the XenServer host control domain backup and restore procedures. These procedures do
not back up the storage repositories that house the VMs, but only the privileged control domain that runs Xen
and the XenServer agent.
Note:
Because the privileged control domain is best left as installed, without customizing it with
other packages, Citrix recommends that you set up a PXE boot environment to cleanly
perform a fresh installation from the XenServer media as a recovery strategy. In many cases
you will not need to backup the control domain at all, but just save the pool metadata (see the