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
Table 3‑1. Features and Devices Incompatible with Fault Tolerance and Corrective Actions
Incompatible Feature or Device Corrective Action
Physical Raw Disk mapping (RDM). With legacy FT you can reconfigure virtual machines with
physical RDM-backed virtual devices to use virtual RDMs
instead.
CD-ROM or floppy virtual devices backed by a physical or
remote device.
Remove the CD-ROM or floppy virtual device or reconfigure the
backing with an ISO installed on shared storage.
USB and sound devices. Remove these devices from the virtual machine.
N_Port ID Virtualization (NPIV). Disable the NPIV configuration of the virtual machine.
NIC passthrough. This feature is not supported by Fault Tolerance so it must be
turned off.
Hot-plugging devices. The hot plug feature is automatically disabled for fault tolerant
virtual machines. To hot plug devices (either adding or
removing), you must momentarily turn off Fault Tolerance,
perform the hot plug, and then turn on Fault Tolerance.
Note When using Fault Tolerance, changing the settings of a
virtual network card while a virtual machine is running is a hot-
plug operation, since it requires "unplugging" the network card
and then "plugging" it in again. For example, with a virtual
network card for a running virtual machine, if you change the
network that the virtual NIC is connected to, FT must be turned
off first.
Serial or parallel ports Remove these devices from the virtual machine.
Video devices that have 3D enabled. Fault Tolerance does not support video devices that have 3D
enabled.
Virtual Machine Communication Interface (VMCI) Not supported by Fault Tolerance.
2TB+ VMDK Fault Tolerance is not supported with a 2TB+ VMDK.
Using Fault Tolerance with DRS
You can use vSphere Fault Tolerance with vSphere Distributed Resource Scheduler (DRS) in vSphere
6.7.
In vSphere 6.7, FT VMs do not require EVC to support DRS. You can use FT with DRS on vSphere 6.5
and 6.0 hosts that are managed by a vSphere 6.7 or higher VC.
Preparing Your Cluster and Hosts for Fault Tolerance
To enable vSphere Fault Tolerance for your cluster, you must meet the feature's prerequisites and you
must perform certain configuration steps on your hosts. After those steps are accomplished and your
cluster has been created, you can also check that your configuration complies with the requirements for
enabling Fault Tolerance.
vSphere Availability
VMware, Inc. 52