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 Select from the following configuration options.
Option Description
Automation Level Determine whether host quarantine or maintenance mode and VM migrations are
recommendations or automatic.
n
Manual. vCenter Server suggests migration recommendations for virtual
machines.
n
Automated. Virtual machines are migrated to healthy hosts and degraded
hosts are entered into quarantine or maintenance mode depending on the
configured Proactive HA automation level.
Remediation Determine what happens to partially degraded hosts.
n
Quarantine mode for all failures. Balances performance and availability, by
avoiding the usage of partially degraded hosts provided that virtual machine
performance is unaffected.
n
Quarantine mode for moderate and Maintenance mode for severe failure
(Mixed). Balances performance and availability, by avoiding the usage of
moderately degraded hosts provided that virtual machine performance is
unaffected. Ensures that virtual machines do not run on severely failed hosts.
n
Maintenance mode for all failures. Ensures that virtual machines do not run
on partially failed hosts.
Host.Config.Quarantine and Host.Config.Maintenance privileges are
required to put hosts in Quarantine mode and Maintenance mode, respectively.
To enable Proactive HA providers for this cluster, select the check boxes. Providers appear when
their corresponding vSphere Web Client plugin has been installed and the providers monitor every
host in the cluster. To view or edit the failure conditions supported by the provider, click the edit link.
7 Click OK.
Configure Admission Control
After you create a cluster, you can configure admission control to specify whether virtual machines can be
started if they violate availability constraints. The cluster reserves resources so that failover can occur for
all running virtual machines on the specified number of hosts.
The Admission Control page appears only if you enabled vSphere HA.
Procedure
1 In the vSphere Client, browse to the vSphere HA cluster.
2 Click the Configure tab.
3 Select vSphere Availability and click Edit.
4 Click Admission Control to display the configuration options.
5 Select a number for the Host failures cluster tolerates. This is the maximum number of host failures
that the cluster can recover from or guarantees failover for.
vSphere Availability
VMware, Inc. 38