Prerequisites for ONTAP SnapMirror active sync
When planning your SnapMirror active sync deployment, ensure you have met the various hardware, software, and system configuration requirements.
Hardware
The following table outlines the supported NetApp cluster configurations.
Cluster type |
Supported models |
Supported features |
Maximum supported cluster nodes |
|---|---|---|---|
AFF |
A-Series, C-Series |
Automated Failover Duplex (asymmetric active/active), Automated Failover (asymmetric active/passive) |
|
ASA |
A-Series, C-Series |
Automated Failover Duplex (symmetric active/active), Automated Failover (asymmetric active/passive) |
|
ASA r2 |
All |
Automated Failover Duplex (symmetric active/active) |
|
The following table outlines the supported NetApp cluster configurations.
| Cluster type | Supported models | Supported features | Maximum supported cluster nodes |
|---|---|---|---|
AFF |
A-Series, C-Series |
Asymmetric active/passive (Automated Failover) |
2 (ONTAP 9.19.1 or later) |
AFX |
All |
Asymmetric active/passive (Automated Failover) |
4 (ONTAP 9.19.1 or later) |
The table below outlines the capability for replication between cluster types.
Cluster type 1 |
Cluster type 2 |
Replication supported? |
|---|---|---|
AFF A-Series |
AFF C-Series |
Yes |
AFF |
AFX |
No |
ASA r2 A-Series |
ASA r2 C-Series |
Yes |
AFF |
ASA |
No |
ASA |
ASA r2 |
No |
Software
-
ONTAP 9.9.1 or later
-
ONTAP Mediator 1.2 or later
-
A Linux server or virtual machine for ONTAP Mediator running one of the following:
ONTAP Mediator version |
Supported Linux versions |
|---|---|
1.12.1 |
|
1.12 |
|
1.11 |
|
1.10 |
|
1.9.1 |
|
1.9 |
|
1.8 |
|
1.7 |
|
1.6 |
|
1.5 |
|
1.4 |
|
1.3 |
|
1.2 |
|
-
Compatible means that Red Hat no longer supports these RHEL versions, but ONTAP Mediator can still be installed on them.
Licensing
The following SnapMirror licenses are available as part of the ONTAP One license suite and must be applied on both clusters:
-
SnapMirror synchronous
-
SnapMirror
If your ONTAP storage systems were purchased before June 2019, see ONTAP license keys to get the required SnapMirror synchronous license. -
For vSphere Metro Storage Cluster (vMSC), a VMware vSphere license is required.
Networking environment
-
Inter-cluster latency round trip time (RTT) must be less than 10 milliseconds.
-
Beginning with ONTAP 9.14.1, SCSI-3 persistent reservations are supported with SnapMirror active sync.
Supported protocols
SnapMirror active sync supports the following SAN protocols.
-
The FC and iSCSI protocols are supported beginning with ONTAP 9.9.1.
-
The NVMe protocol is supported with VMware workloads beginning with ONTAP 9.17.1.
SnapMirror active sync does not support the following with the NVMe protocol:
-
4-node symmetric active/active configurations
-
Asymmetric active/passive configurations
-
Changes in consistency group size
You cannot expand or shrink a consistency group non-disruptively when using the NVMe protocol with SnapMirror active sync. Consistency group expansion and shrink operations are disruptive when using the NVMe protocol with SnapMirror active sync.
-
Coexistence of LUNs and namespaces in the same consistency group.
-
Beginning with ONTAP 9.19.1, SnapMirror active sync supports the following NAS protocols.
-
NFSv3 and later
Non-disruptive failover is supported for NFSv3 and later.
-
SMB
-
Non-disruptive failover is supported for SMB 3 CA shares.
-
Disruptive (but zero RPO maintained) failover is supported for SMB2 and SMB3 non-CA shares.
-
SMB1 is not supported.
-
NAS clusters require the same IP address and protocol configuration on the primary and secondary cluster to enable non-disruptive failover. Because SVMs can be configured with the same IP address and protocols, SnapMirror active sync supports NAS configurations at the SVM level; however, the secondary SVM remains dormant (not running) because the LIFs must remain down until a failover occurs to prevent IP collision with the primary SVM.
IPspace
The default IPspace is required by SnapMirror active sync for cluster peer relationships. Custom IPspaces are not supported.
With SnapMirror active sync for NAS, primary and secondary SVMs can be in different IPspaces.
NTFS Security Style
NTFS security style is not supported on SnapMirror active sync volumes for SAN. NTFS Security Style is supported with SnapMirror active sync for NAS.
ONTAP Mediator
-
ONTAP Mediator must be provisioned externally and attached to ONTAP for transparent application failover.
-
To be fully functional and to enable automatic unplanned failover, the external ONTAP Mediator should be provisioned and configured with ONTAP clusters.
-
ONTAP Mediator must be installed in a third failure domain, separate from the two ONTAP clusters.
-
When installing ONTAP Mediator, you should replace the self-signed certificate with a valid certificate signed by a mainstream reliable CA.
-
For more information about ONTAP Mediator, see Prepare to install ONTAP Mediator.
Other prerequisites
-
In releases earlier than ONTAP 9.15.1, SnapMirror active sync relationships are not supported on read-write destination volumes (volumes converted to read-write from DP in an asymmetric active-passive). Before you can use a read-write volume, you must convert it to a DP volume by creating a volume-level SnapMirror relationship (either async or sync) and then deleting the relationship. For details, see Convert an existing SnapMirror relationships to SnapMirror active sync.
-
Storage VMs using SnapMirror active sync cannot be joined to Active Directory as a client computer.