FAQ: vCenter High Availability

Products

VMware vCenter Server

Issue/Introduction

This article provides information on some of the frequently asked questions about vCenter High Availability (VCHA). vCenter HA protects the vCenter Server Appliance against host and hardware failures. The active-passive architecture allows to reduce significant downtime when patching the vCenter Server Appliance.

VCHA is not a disaster recovery product such as Site Recovery Manager and VMware vSphere Replication.

For more information see the vCenter High Availability section of the vSphere Availability guide.

Environment

VMware vCenter Server 8.0.x

VMware vCenter Server 7.0.x
VMware vCenter Server Appliance 6.5.x
VMware vCenter Server Appliance 6.7.x

Resolution

Can vCenter HA nodes be deployed across vCenter Datacenters?

vCenter HA can be deployed across three vCenter Datacenter Managed Objects in the vCenter Server Inventory.
VMware does not support nor recommend deploying vCenter HA over a WAN configuration.
Deployment of nodes across geographically dispersed datacenters is also unsupported.
Network latency between the Active, Passive, and Witness nodes must have less than 10 milliseconds and a minimum of a 1 Gbps network. This requirement is for a high-bandwidth/low-latency network for the replication traffic.
For more information, see Deploying vCenter High Availability with network addresses in separate subnets.

Can the Passive Nodes Management Address be changed?

Yes. This can be accomplished in both a basic and advanced deployment of VCHA. For more details see Deploying vCenter High Availability with network addresses in separate subnets. If the address needs to be changed after VCHA is configured, VCHA must be reconfigured per below.

Can the hostname or IP address of a VCHA enabled node be changed?

No. While vCenter HA is enabled, no changes can be made to the addresses or hostnames of the nodes.

Can SSH be disabled after the initial deployment of VCHA?

No. SSH is required for rsync, which replicates files between the active and passive nodes.

ESXi hosts disconnect on vCenter HA failover if your Active and Passive nodes have different management IP's.

Ensure that the vCenter Server managed address setting is not set to an IP address. To verify the vCenter Server managed address follow the steps below:

Log into the vSphere Web Client.
Select the Hosts and Clusters view.
Select the vCenter Server in the left hand pane.
Select the Configure tab.
Make sure General is highlighted under the Settings drop down list.
Expand Runtime settings.
Ensure the vCenter Server managed address is not set to an IP address.

Can I use a multi-homed NIC for my VCHA and Management networks?

Multi-homed NICs are not supported in a VCHA configuration. Please use separate NICs for each network. For more information, see Multi-Homing NICs are not supported when using VCHA.

Do I need more than one vCenter Server license to use VCHA?

No. Only a single vCenter Server license is required to use VCHA.

Are snapshots, cloning, and Fault Tolerance supported on VCHA nodes?

No, it's currently not supported to use these operations on any of the VCHA nodes.

Note: File-Based backups of the VCHA Active node are supported. Do not backup or restore the Passive and Witness nodes. Image-Based backups of the Active VCHA node are not supported. Image-Based backups use snapshots during the process which could cause a failover in environments with high latency, and may result in an inconsistent state on the restored vCenter.

For more information on proper backup and restore practices in a vCenter HA environment, See vSphere Availability - VMware vSphere 8.0 under Perform Backup and Restore Operations.

Can a vCenter Server be upgraded without removing VCHA?

Starting in vCenter Server 8.0 Update 3, the Reduced Disruption Upgrade (RDU) method of patching allows a vCenter Server configured with a Basic VCHA configuration to be upgraded without first destroying the VCHA cluster. In any other scenario, the vCenter HA configuration should be removed prior to upgrades.

Can VCHA be deployed without a load balanced 6.x PSC configuration?

Load balanced PSCs are required for VCHA unless the PSC in embedded into the vCenter Server Appliance. For more information on deployment types, see the vCenter HA Deployment Options section in the vSphere Availability guide.

Can I repoint a vCenter HA node to another 6.x PSC?

Repointing a vCenter Server in a VCHA cluster is not supported. Destroying VCHA is necessary

Before performing a domain repoint.
Repointing to a new PSC or domain.

Additional Information

VMware Skyline Health Diagnostics for vSphere - FAQ