10:12 a.m.
Hi Jonas, when migrating Gluster volumes from one cluster to another, there are a few
approaches you can consider. While Red Hat primarily recommends replacing old bricks,
there are alternative methods you can explore. One such approach involves recreating the
volumes on the new cluster and using rsync to synchronize the data between the old and new
clusters. Here's a step-by-step outline of this migration strategy:
1.Set up the new oVirt cluster and ensure it is properly configured and operational.
2.Create empty Gluster volumes on the new cluster with the same configuration (stripe
count, replica count, etc.) as the volumes on the old cluster. You can use the Gluster
command-line tools or the oVirt management interface to create the volumes.
3.Install rsync on both the old and new clusters if it's not already available. You
can use your distribution's package manager to install it.
4.Stop any read/write operations on the volume you wish to migrate on the old cluster.
This will ensure data consistency during the migration process.
5.Initiate an initial rsync operation from the old cluster to the new cluster to copy the
data from the old volume to the newly created volume on the new cluster. The command would
look something like this:
rsync -avhP /path/to/old/volume/ user@new_cluster:/path/to/new/volume/
```
This command will synchronize the data between the old and new volumes. You may need to
adjust the paths and SSH details to match your setup.
6.Once the initial rsync is complete, you can perform incremental rsync operations to
synchronize any changes that occurred on the old volume during the initial copy process.
You can schedule these incremental rsyncs at regular intervals or use tools like cron to
automate the process.
7.At a predetermined point in time when you're ready to cut over to the new cluster,
stop the application or any processes that are accessing the old volume to ensure data
integrity during the final synchronization.
8.Perform a final rsync operation to copy any remaining changes from the old volume to the
new volume. This ensures that both volumes are in sync before the cutover. The command
would be similar to the initial rsync operation.
9.Once the final rsync is complete, unmount the old volume from the application servers
and mount the new volume at the same path.
10.Start the application or processes that were using the old volume, and ensure they are
now accessing the new volume on the new cluster.
By following this approach, you can migrate Gluster volumes from one cluster to another
while minimizing downtime and ensuring data consistency. Vinchin Backup & Recovery is
a powerful data protection solution that supports a wide range of virtual environments,
including oVirt. It can be a very useful tool when migrating Gluster volumes from one
oVirt cluster to another. Remember to test this process in a non-production environment
and have proper backups of your data before proceeding with the migration.