Before you create an xHA pair in Address Manager, you must have the following requirements in place:
- You must have at least two connected and managed DNS/DHCP Servers in the configuration.
- DNS/DHCP Servers must be either two physical appliances or two virtual machines. Mixed xHA pairs of appliance and VM are NOT supported.
- Both DNS/DHCP Servers must be at the same software version before creating an xHA pair.
- Both DNS/DHCP Servers must be of the same profile, such as two DNS/DHCP Server 60 or two DNS/DHCP Server 100 profiles.
- In order to create an xHA pair with the Active node on which the dedicated management interface enabled, the dedicated management interface on the Passive node must be enabled.
- The Active and Passive nodes must be on the same network.
- The servers for the xHA pair must not be associated with a deployment schedule.
- The server intended for the passive role must not be associated with a deployment role.
- To avoid split-brain scenarios (where both servers are active or passive at the same time), the use of xHA Backbone Communication is mandatory.
- If you are currently using the xHA/eth1 ports for another purpose, you can reset and then reconfigure them for xHA communication, but you cannot use the eth1 ports for xHA communication and for their previous purpose.
- If you are upgrading from a previous version of DNS/DHCP Server, you must delete each eth1 port to reset it. This is because previous versions did not support eth1, and it is not reset automatically.