There is a SLIGHT difference between ESXi host isolation and network partitioned. When multiple slave ESXi hosts has isolated together but they can ping each other than this condition is known as network partitioned.

For e.g.: Subnet mask of 5 ESXi has been changed then they will be UNABLE to talk to master (being on different SUBNETS) but they can communicate to each other (being on same subnet).

When network partitioned happens in a cluster then election happens between the isolated slaves ESXi and a new master is ELECTED among them. In this case there will be 2 masters in a cluster.

There is a slight difference between ESXi host isolation and network partitioned. When multiple slave ESXi hosts has isolated together but they can ping each other than this condition is known as network partitioned.

For e.g.: Subnet mask of 5 ESXi has been changed then they will be unable to talk to master (being on different subnets) but they can communicate to each other (being on same subnet).

When network partitioned happens in a cluster then election happens between the isolated slaves ESXi and a new master is elected among them. In this case there will be 2 masters in a cluster.