A good disaster recovery (DR) failover plan is essential for all IT organizations large and small to ensure business continuity in the event of power outages, network outages and natural disasters that can impact the availability of systems.
QuantaStor software-defined storage platform makes it easy to implement a DR strategy using Remote Replication Schedules. Each replication schedule specifies what to replicate (Storage Volumes and/or Network Shares) and the destination Storage Pool where they are to be replicated to.
Beyond that replication schedules have an important feature for protecting your organization against ransomware and that’s the ‘Long Term Snapshot Retention Rules’. This allows one to indicate how many daily, weekly, monthly, and quarterly snapshots are to be retained and rotated through as the schedule runs over time. Retaining multiple quarterly snapshots is especially important as some ransomware attacks can happen long before an IT organization may become aware of the security breach.
Automating DR Failover
With the upcoming release of QuantaStor 5.10 a new feature has been added to fully automate that activation of a DR site in the event of an outage at the primary site. This is easily setup by creating a ‘Site Cluster’ in the ‘High-availability VIF Management’ section within the QuantaStor web management interface.
The Site Cluster can include any number of systems within a QuantaStor storage grid but must include the source and destination systems indicated in the Remote Replication schedule.
Once the Site Cluster has been established a VIF can be added to the cluster and bound to a physical interface, in this case ens192. When the VIF moves to the other DR site system it will bind to the physical port with the same name, ens192.
Once the VIF has been created, bring up the ‘Modify Remote Replication Schedule’ dialog in the ‘Automatic Activation’ tab ‘[x] Enable Automatic Checkpoint Activation’ and choose the newly created VIF from the list. After pressing OK to apply the changes the Replication Schedule is now ready to automatically activate all checkpoints anytime the VIF arrives on the system where the destination Storage Pool resides.
You can test this by selecting the VIF in the ‘High-availability VIF Management’ section and then choosing the menu option to move the VIF to the destination system.
Once the VIF arrives you’ll notice the Checkpoint Activation task start and the Replication Schedule will transition to the Offline state.
If you need to script additional steps as part of the site failover, QuantaStor provides the ability to add your own custom scripts to the process. To script actions at the start of the failover task one would add a DR Pre-failover script. To script actions after the checkpoints have been activated (eg: NFS mounts, starting databases, etc) one would add a custom DR Post-failover script.
To resume replication simply move the VIF back to the primary site and then use the ‘Deactivate Checkpoints’ option on the Replication Schedule to resume regular replication to the DR site.
Once resumed any changes made to the DR site Network Share and Storage Volume checkpoints (these contain _chkpnt suffix) will be discarded. As such be sure to copy changes to be retained back to the primary side before resuming replication. For more information on how to do data roll-back from the DR site and how to configure remote replication in QuantaStor, see our online documentation here.
Hope you enjoyed the article and if you have any questions feel free to write us at info@osnexus.com.
Categories: Storage Appliance Hardware
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