6.7
Table Of Contents
- vSphere Availability
- Contents
- About vSphere Availability
- Business Continuity and Minimizing Downtime
- Creating and Using vSphere HA Clusters
- Providing Fault Tolerance for Virtual Machines
- How Fault Tolerance Works
- Fault Tolerance Use Cases
- Fault Tolerance Requirements, Limits, and Licensing
- Fault Tolerance Interoperability
- Preparing Your Cluster and Hosts for Fault Tolerance
- Using Fault Tolerance
- Best Practices for Fault Tolerance
- Legacy Fault Tolerance
- Troubleshooting Fault Tolerant Virtual Machines
- Hardware Virtualization Not Enabled
- Compatible Hosts Not Available for Secondary VM
- Secondary VM on Overcommitted Host Degrades Performance of Primary VM
- Increased Network Latency Observed in FT Virtual Machines
- Some Hosts Are Overloaded with FT Virtual Machines
- Losing Access to FT Metadata Datastore
- Turning On vSphere FT for Powered-On VM Fails
- FT Virtual Machines not Placed or Evacuated by vSphere DRS
- Fault Tolerant Virtual Machine Failovers
- vCenter High Availability
- Plan the vCenter HA Deployment
- Configure the Network
- Configure vCenter HA With the Basic Option
- Configure vCenter HA With the Advanced Option
- Manage the vCenter HA Configuration
- Set Up SNMP Traps
- Set Up Your Environment to Use Custom Certificates
- Manage vCenter HA SSH Keys
- Initiate a vCenter HA Failover
- Edit the vCenter HA Cluster Configuration
- Perform Backup and Restore Operations
- Remove a vCenter HA Configuration
- Reboot All vCenter HA Nodes
- Change the Appliance Environment
- Collecting Support Bundles for a vCenter HA Node
- Troubleshoot Your vCenter HA Environment
- Patching a vCenter High Availability Environment
- Using Microsoft Clustering Service for vCenter Server on Windows High Availability
6 Troubleshoot Your vCenter HA Environment
In case of problems you can troubleshoot your environment. The task you need to perform depends
on the failure symptoms. For additional troubleshooting information, see the VMware Knowledge
Base system.
7 Patching a vCenter High Availability Environment
You can patch a vCenter Server Appliance which is in a vCenter High Availability cluster by using
the <codeph>software-packages</codeph> utility available in the vCenter Server Appliance shell.
For more information, see vSphere Upgrade.
Plan the vCenter HA Deployment
Before you can configure vCenter HA, you have to consider several factors. A vCenter Server Appliance
deployment can use an internal or external Platform Services Controller. A brownfield deployment with
components that use different versions of vSphere requires different considerations than a greenfield
deployment that includes only vSphere 6.5 components. Resource and software requirements and the
networking setup must also be considered carefully.
vCenter Architecture Overview
A vCenter HA cluster consists of three vCenter Server Appliance instances. The first instance, initially
used as the Active node, is cloned twice to a Passive node and to a Witness node. Together, the three
nodes provide an active-passive failover solution.
Deploying each of the nodes on a different ESXi instance protects against hardware failure. Adding the
three ESXi hosts to a DRS cluster can further protect your environment.
When vCenter HA configuration is complete, only the Active node has an active management interface
(public IP). The three nodes communicate over a private network called vCenter HA network that is set up
as part of configuration. The Active node and the Passive node are continuously replicating data.
Figure 4‑1. vCenter Three-Node Cluster
vCenter (Active)
HA Interface
vCenter (Passive)
Witness
vCenter HA
Network
HA Interface
Mgmt Interface
All three nodes are necessary for the functioning of this feature. Compare the node responsibilities.
vSphere Availability
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