VxRail supports a solution for small-scale deployments with reduced workload and availability requirements, such as those in a remote office setting. The solution is limited to two VxRail nodes only, and like the stretched cluster solution, requires a witness for monitoring purposes.
If you plan to deploy 2-node VxRail clusters, note the following:
- The minimum VxRail software version for the 2-node cluster is 4.7.100.
- The deployment is limited to a pair of VxRail nodes.
- Verify that your workload requirements do not exceed the resource capacity of this small-scale solution.
- You cannot expand to three or more nodes unless the cluster is running version 7.0.130 or later.
- A single top-of-rack switch is supported.
- Four Ethernet ports per node are required to deploy a 2-node cluster. Supported networking options:
- Four 10GbE NICs
- Four 25GbE NICs
- Two 10GbE NICs and two 25GbE NICs
- Two 1GbE NICs and two 10GbE NICs
- Two 1GbE NICs and two 25GbE NICs
- In a mixed network configuration, the vSAN network must be placed on the pair of Ethernet ports running at the higher speed
- A 2-node cluster can be deployed with one of two network topologies
- Two Ethernet ports connect to create two links between the physical VxRail nodes, and the other two Ethernet ports connect to the top-of-rack switch
Figure 26. Direct connect option for a 2-node cluster
- All four Ethernet ports connect to the top-of-rack switch or switches
Figure 27. Switch-only option for a 2-node cluster
The following guidelines must be followed for the required Witness
- Network connectivity is required between the 2-node cluster and the Witness.
- Witness can be deployed at the same physical site as the VxRail nodes but cannot be deployed on the 2-node cluster.
- For instances where there are more than one 2-node clusters deployed at the site, the Witness can reside on a 2-node cluster it is not monitoring.
- For a 2-node cluster based on the VxRail XR-Series hardware, targeted for edge use cases:
- The witness sled integrated into the XR-Series chassis can support only one VxRail 2-node cluster.
- The Ethernet ports on the witness sled supporting the 2-node cluster only support 1 GbE
Figure 28. 2-Node cluster on XR-Series compute sleds and a witness sled
- The vCenter instance supporting the 2-node cluster can be either a VxRail-supplied vCenter deployed on the cluster, or a customer-supplied vCenter external to the 2-node cluster
- A minimum VxRail version of 7.0.410 is required for the VxRail-supplied vCenter option
Figure 29. Two vCenter placement options for a 2-node cluster
Like the vSAN stretched cluster feature, this small-scale solution has strict networking guidelines that must be adhered to for the solution to work. For more information about the planning and preparation for a deployment of a 2-node VxRail cluster, see the Planning Guide—vSAN 2-Node Cluster on VxRail.