Backup site for vSZ-H

Question

We have a vSZ-H running 3.4.0.0.976 at one of Private data centers.We are planning to install another one at a different location as a backup for the existing one.So I have few questions regarding the deployment. 
-Do we need additional licenses? 
-Do we need to take anything in consideration before deployment or do we deploy it as the previous one and configure it as a slave/backup later? 
-What are the requirements for WAN as they would be on different locations and hence different subnet?

unknown · Answer

Now that we are deploying it as per the guide,we followed each and every steps stated in the guide but the GUI is unreachable from Management interface IP:8443 of vSZ we can only SSH it from Control IP.Is there anything we might have missed ? It is configured using three interfaces and for the time being all three IPs are in same subnet.Any suggestions are welcome.

michael_brado · Answer

Your second vSZ-H only needs RTU and Support, not additional AP license.
They both recognize and backup each other, no master/slave config necessary.
Define a new AP zone for the different locations with different subnet WLANs.
(these are replicated on both vSZs)