Chapter 6. Backing up and Restoring a Self-Hosted Engine
You can back up a self-hosted engine and restore it in a new self-hosted environment. Use this procedure for tasks such as migrating the environment to a new self-hosted engine storage domain with a different storage type.
When you specify a backup file during deployment, the backup is restored on a new Manager virtual machine, with a new self-hosted engine storage domain. The old Manager is removed, and the old self-hosted engine storage domain is renamed and can be manually removed after you confirm that the new environment is working correctly. Deploying on a fresh host is highly recommended; if the host used for deployment existed in the backed up environment, it will be removed from the restored database to avoid conflicts in the new environment.
The backup and restore operation involves the following key actions:
Back up the original Manager using the
- Deploy a new self-hosted engine and restore the backup.
- Enable the Manager repositories on the new Manager virtual machine.
- Reinstall the self-hosted engine nodes to update their configuration.
- Remove the old self-hosted engine storage domain.
This procedure assumes that you have access and can make changes to the original Manager.
- A fresh installation of Red Hat Virtualization Host or Red Hat Enterprise Linux 7, with the required repositories enabled. See Installing Red Hat Virtualization Host or Enabling the Red Hat Enterprise Linux Host Repositories in the Installation Guide.
- A fully qualified domain name prepared for your Manager and the host. Forward and reverse lookup records must both be set in the DNS. The new Manager must have the same fully qualified domain name as the original Manager.
- A directory of at least 5 GB on the host, for the RHV-M Appliance. The deployment process will check if /var/tmp has enough space to extract the appliance files. If not, you can specify a different directory or mount external storage. The VDSM user and KVM group must have read, write, and execute permissions on the directory.
Prepared storage for a data storage domain dedicated to the Manager virtual machine. This storage domain is created during the self-hosted engine deployment, and must be at least 74 GiB. Highly available storage is recommended. For more information on preparing storage for your deployment, see the Storage chapter of the Administration Guide.Warning
If you are using NFS or Gluster storage, do not use the old self-hosted engine storage domain’s mount point to deploy the new storage domain, as you risk losing virtual machine data.Important
If you are using iSCSI storage, the self-hosted engine storage domain must use its own iSCSI target. Any additional storage domains must use a different iSCSI target.
- The original Manager must be updated to the latest minor version; the Manager version in the backup file must match the version of the new Manager. See Updating the Red Hat Virtualization Manager in the Upgrade Guide.
There must be at least one regular host in the environment. This host (and any other regular hosts) will remain active to host the SPM role and any running virtual machines. If a regular host is not already the SPM, move the SPM role before creating the backup by selecting a regular host and clicking Management → Select as SPM.
If no regular hosts are available, there are two ways to add one:
- Remove the self-hosted engine configuration from a node (but do not remove the node from the environment). See Section 4.6, “Removing a Host from a Self-Hosted Engine Environment”.
- Add a new regular host. See Adding a Host to the Red Hat Virtualization Manager in the Installation Guide.
6.1. Backing up the Original Manager
Back up the original Manager using the
engine-backup command, and copy the backup file to a separate location so that it can be accessed at any point during the process.
For more information about
engine-backup --mode=backup options, see Backing Up and Restoring the Red Hat Virtualization Manager in the Administration Guide.
Log in to one of the self-hosted engine nodes and move the environment to global maintenance mode:
# hosted-engine --set-maintenance --mode=global
Log in to the original Manager and stop the
# systemctl stop ovirt-engine # systemctl disable ovirt-engineNote
Though stopping the original Manager from running is not obligatory, it is recommended as it ensures no changes are made to the environment after the backup is created. Additionally, it prevents the original Manager and the new Manager from simultaneously managing existing resources.
engine-backupcommand, specifying the name of the backup file to create, and the name of the log file to create to store the backup log:
# engine-backup --mode=backup --file=file_name --log=log_file_name
Copy the files to an external server. In the following example,
storage.example.comis the fully qualified domain name of a network storage server that will store the backup until it is needed, and
/backup/is any designated folder or path.
# scp -p file_name log_file_name storage.example.com:/backup/
If you do not require the Manager machine for other purposes, unregister it from Red Hat Subscription Manager:
# subscription-manager unregister
Log in to one of the self-hosted engine nodes and shut down the original Manager virtual machine:
# hosted-engine --vm-shutdown
After backing up the Manager, deploy a new self-hosted engine and restore the backup on the new virtual machine.