6.7

Table Of Contents
Solution
Resolve the networking problem that prevents the hosts from communicating by using the management
networks.
vSphere HA Agent is in the Network Isolated State
The vSphere HA agent on a host is in the Network Isolated state. User intervention is required to resolve
this situation.
Problem
When a host is in the Network Isolated state, there are two things to consider -- the isolated host and the
vSphere HA agent that holds the master role.
n
On the isolated host, the vSphere HA agent applies the configured isolation response to the running
VMs, determining if they should be shut down or powered off. It does this after checking whether a
master agent is able to take responsibility for each VM (by locking the VM's home datastore.) If not,
the agent defers applying the isolation response for the VM and rechecks the datastore state after a
short delay.
n
If the vSphere HA master agent can access one or more of the datastores, it monitors the VMs that
were running on the host when it became isolated and attempts to restart any that were powered off
or shut down.
Cause
A host is network isolated if both of the following conditions are met:
n
Isolation addresses have been configured and the host is unable to ping them.
n
The vSphere HA agent on the host is unable to access any of the agents running on the other cluster
hosts.
Note If your vSphere HA cluster has vSAN enabled, a host is determined to be isolated if it cannot
communicate with the other vSphere HA agents in the cluster and cannot reach the configured isolation
addresses. Although the vSphere HA agents use the vSAN network for inter-agent communication, the
default isolation address is still the gateway of the host. Hence, in the default configuration, both networks
must fail for a host be declared isolated.
Solution
Resolve the networking problem that is preventing the host from pinging its isolation addresses and
communicating with other hosts.
Configuration of vSphere HA on Hosts Times Out
The configuration of a vSphere HA cluster might time out on some of the hosts added to it.
vCenter Server and Host Management
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