A 2-node cluster supports 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.
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 ToR switch is supported.
- Four Ethernet ports per node are required to deploy a 2-node cluster. Supported networking options include:
- Four 10 GbE NICs.
- Four 25 GbE NICs.
- Two 10 GbE NICs and two 25 GbE NICs.
- Two 1 GbE NICs and two 10 GbE NICs.
- Two 1 GbE NICs and two 25 GbE 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 ToR switch.
Figure 26. Direct connect option for a 2-node cluster. Direct connect option for a 2-node cluster - All four Ethernet ports connect to the ToR switch or switches.
Figure 27. Switch-only option for a 2-node cluster. Switch-only option for a 2-node cluster
- Two Ethernet ports connect to create two links between the physical VxRail nodes, and the other two Ethernet ports connect to the ToR switch.
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.
- If there is 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 VD-Series compute sleds and a witness sled. 2-node cluster on VD-Series compute sleds and a witness sled
- The VMware vCenter Server instance supporting the 2-node cluster can be either a VxRail-managed VMware vCenter Server deployed on the cluster, or a customer-managed VMware vCenter Server external to the 2-node cluster. A minimum VxRail version of 7.0.410 is required for the VxRail supplied VMware vCenter option.
Figure 29. Two VMware vCenter Server placement options for a 2-node cluster. Two VMware vCenter Server placement options for a 2-node cluster
Like the VMware 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 GuideāvSAN 2-Node Cluster on VxRail.