6.5.1

Table Of Contents
vSphere HA and DRS Affinity Rules
If you create a DRS anity rule for your cluster, you can specify how vSphere HA applies that rule during a
virtual machine failover.
The two types of rules for which you can specify vSphere HA failover behavior are the following:
n
VM anti-anity rules force specied virtual machines to remain apart during failover actions.
n
VM-Host anity rules place specied virtual machines on a particular host or a member of a dened
group of hosts during failover actions.
When you edit a DRS anity rule, select the checkbox or checkboxes that enforce the desired failover
behavior for vSphere HA.
n
HA must respect VM  rules during failover -- if VMs with this rule would be placed
together, the failover is aborted.
n
HA should respect VM to Host  rules during failover --vSphere HA aempts to place VMs
with this rule on the specied hosts if at all possible.
N vSphere HA can restart a VM in a DRS-disabled cluster, overriding a VM-Host anity rules
mapping if the host failure happens soon (by default, within 5 minutes) after seing the rule.
Other vSphere HA Interoperability Issues
To use vSphere HA, you must be aware of the following additional interoperability issues.
VM Component Protection
VM Component Protection (VMCP) has the following interoperability issues and limitations:
n
VMCP does not support vSphere Fault Tolerance. If VMCP is enabled for a cluster using Fault
Tolerance, the aected FT virtual machines will automatically receive overrides that disable VMCP.
n
VMCP does not detect or respond to accessibility issues for les located on vSAN datastores. If a virtual
machine's conguration and VMDK les are located only on vSAN datastores, they are not protected
by VMCP.
n
VMCP does not detect or respond to accessibility issues for les located on Virtual Volume datastores. If
a virtual machine's conguration and VMDK les are located only on Virtual Volume datastores, they
are not protected by VMCP.
n
VMCP does not protect against inaccessible Raw Device Mapping (RDM)s.
IPv6
vSphere HA can be used with IPv6 network congurations, which are fully supported if the following
considerations are observed:
n
The cluster contains only ESXi 6.0 or later hosts.
n
The management network for all hosts in the cluster must be congured with the same IP version,
either IPv6 or IPv4. vSphere HA clusters cannot contain both types of networking conguration.
n
The network isolation addresses used by vSphere HA must match the IP version used by the cluster for
its management network.
n
IPv6 cannot be used in vSphere HA clusters that also utilize vSAN.
vSphere Availability
26 VMware, Inc.