Requirements and considerations for Azure NetApp Files replication

Before you configure cross-zone or cross-region replication, make sure that you understand the requirements for each option.

If you use cross-zone-region replication, you must adhere to all the requirements.

Shared requirements for cross-zone and cross-region replication

• Azure NetApp Files replication is supported within a subscription and between subscriptions under the same tenant. To enable replication across subscriptions, you must register the feature.

• Cross-zone and cross-region replication are supported with both Network File System (NFS) and Server Message Block (SMB) volumes.

  Replication of SMB volumes requires an Active Directory (AD) connection in the source and the destination NetApp accounts. The destination AD connection must have access to the Domain Name System (DNS) servers or the Active Directory Domain Services (AD DS) domain controllers that are reachable from the delegated subnet in the destination zone. For more information, see Requirements for AD connections.

• To mount a dual-protocol volume, you must first authorize replication from the source volume, and the initial transfer happens.

• Consult resource limits for the maximum number of destination volumes that you can create. You can open a support ticket to request a limit increase in the default quota of replication destination volumes for each subscription in a region.

• Cascading and fan-in topologies aren't supported. To learn about support for fan-out deployments, see Configure cross-zone-region replication.

• Data replication volumes support customer-managed keys.

• Large volumes are supported with cross-zone replication only with an hourly or daily replication schedule.

• After you establish replication, the replication process creates SnapMirror snapshots to provide references between the source volume and the destination volume. SnapMirror snapshots are cycled automatically when a new one is created for every incremental transfer. You can't delete SnapMirror snapshots until you delete the replication relationship and volume.

• The interface might take up to five minutes to reflect a newly added snapshot on the source volume.

• You can delete manual snapshots on the source volume of a replication relationship when the replication relationship is active or broken. You can also delete manual snapshots after you delete the replication relationship. You can't delete manual snapshots for the destination volume until you break the replication relationship.

Cross-zone replication requirements and considerations

• The cross-zone replication feature uses the availability zone volume placement feature of Azure NetApp Files.

• To establish cross-zone replication, you must create the source volume in an availability zone.

• To replicate to a destination volume in another NetApp account, the destination volume must be in a different zone than the source volume.

• The destination volume is read-only until you fail over to the destination zone to enable the destination volume for read and write. For more information about the failover process, see Fail over to the destination volume.

  Important

  Failover is a manual process. When you need to activate the destination volume (like when you want to fail over to the destination region), you first need to break replication peering and then mount the destination volume. For more information, see Fail over to the destination volume.

• When you revert a source volume that has an active volume replication relationship, only snapshots dated more recently than the SnapMirror snapshot can be used in the revert operation. For more information, see Revert a volume by using snapshot revert with Azure NetApp Files.

Cross-region replication requirements and considerations

• Azure NetApp Files replication is only available in specific fixed region pairs. For more information, see Supported cross-region replication pairs.

• Cross-region replication requires a NetApp account in the destination region.

• The replication destination volume is read-only until you fail over to the destination region to enable the destination volume for read and write.

  Important

  Failover is a manual process. When you need to activate the destination volume (like when you want to fail over to the destination region), you need to break replication peering and then mount the destination volume. For more information, see Fail over to the destination volume.

  Important

  A volume that has an active backup policy enabled can't be the destination volume in a reverse resync operation. You must suspend the backup policy on the volume before you start the reverse resync. You can resume the backup policy when the reverse resync completes.

• You can revert a source or destination volume of a cross-region replication to a snapshot if the snapshot is newer than the most recent SnapMirror snapshot. You can't use snapshots that are older than the SnapMirror snapshot for a volume revert operation. For more information, see Revert a volume by using snapshot revert.

• If you copy large datasets into a volume that has cross-region replication enabled and you have spare capacity in the capacity pool, you should take the following actions:

  • Set the replication interval to 10 minutes.
  • Increase the volume size so that the changes can be stored.
  • Temporarily disable replication.

• You can revert a source or destination volume of a cross-region replication to a snapshot if the snapshot is newer than the most recent SnapMirror snapshot. You can't use snapshots that are older than the SnapMirror snapshot for a volume revert operation. For more information, see Revert a volume by using snapshot revert.

• If you copy large datasets into a volume that has cross-region replication enabled and you have spare capacity in the capacity pool, you should set the replication interval to 10 minutes, increase the volume size to allow for the changes to be stored, and temporarily disable replication.

• If you use the cool access feature, understand the considerations in Manage Azure NetApp Files storage with cool access.

• If the volume's size exceeds 95% utilization, there's a risk that replication to the destination volume can fail, depending on the rate of data changes.

Supported cross-region replication pairs

Azure NetApp Files volume replication is supported between various Azure regional pairs and nonstandard pairs. Azure NetApp Files volume replication is currently available between the following regions. You can replicate Azure NetApp Files volumes from Regional Pair A to Regional Pair B and from Regional Pair B to Regional Pair A.

Azure regional pairs

Azure regional nonstandard pairs

Next steps

• Create volume replication
• Create cross-zone replication relationships
• Display health status of replication relationship
• Manage disaster recovery
• Volume replication metrics
• Delete volume replications or volumes
• Troubleshoot cross-region replication errors
• Revert a volume by using snapshot revert with Azure NetApp Files
• Test disaster recovery for Azure NetApp Files