6.5.1
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
- 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
- Index
Best Practices for VMware vSphere
®
High Availability Clusters
To ensure optimal vSphere HA cluster performance, you must follow certain best practices. This section
highlights some of the key best practices for a vSphere HA cluster.
You can also refer to the vSphere High Availability Deployment Best Practices publication for further discussion.
Best Practices for Networking
Observe the following best practices for the conguration of host NICs and network topology for vSphere
HA. Best Practices include recommendations for your ESXi hosts, and for cabling, switches, routers, and
rewalls.
Network Configuration and Maintenance
The following network maintenance suggestions can help you avoid the accidental detection of failed hosts
and network isolation because of dropped vSphere HA heartbeats.
n
When changing the networks that your clustered ESXi hosts are on, suspend the Host Monitoring
feature. Changing your network hardware or networking seings can interrupt the heartbeats that
vSphere HA uses to detect host failures, which might result in unwanted aempts to fail over virtual
machines.
n
When you change the networking conguration on the ESXi hosts themselves, for example, adding port
groups, or removing vSwitches, suspend Host Monitoring. After you have made the networking
conguration changes, you must recongure vSphere HA on all hosts in the cluster, which causes the
network information to be reinspected. Then re-enable Host Monitoring.
N Because networking is a vital component of vSphere HA, if network maintenance must be performed
inform the vSphere HA administrator.
Networks Used for vSphere HA Communications
To identify which network operations might disrupt the functioning of vSphere HA, you must know which
management networks are being used for heart beating and other vSphere HA communications.
n
On legacy ESX hosts in the cluster, vSphere HA communications travel over all networks that are
designated as service console networks. VMkernel networks are not used by these hosts for vSphere
HA communications. To contain vSphere HA trac to a subset of the ESX console networks, use the
allowedNetworks advanced option.
n
On ESXi hosts in the cluster, vSphere HA communications, by default, travel over VMkernel networks.
With an ESXi host, if you want to use a network other than the one vCenter Server uses to communicate
with the host for vSphere HA, you must explicitly enable the Management check box.
To keep vSphere HA agent trac on the networks you have specied, congure hosts so vmkNICs used by
vSphere HA do not share subnets with vmkNICs used for other purposes. vSphere HA agents send packets
using any pNIC that is associated with a given subnet when there is also at least one vmkNIC congured for
vSphere HA management trac. Therefore, to ensure network ow separation, the vmkNICs used by
vSphere HA and by other features must be on dierent subnets.
vSphere Availability
38 VMware, Inc.