Moving CUCM pub and sub to another location

[Abdelrhman Elmenyawe]

I have a cluster of Pub and two subscribers.

What will be the best method to move the PUB and SUB-1 to another location, as well as changing their IP addresses?

should I change the IP of pub and sub first, then shut down the VMs and move them to the second location?

but if i do this method, the network connectivity between nodes will be affected and the SUB-2 will lose connection to pub.

or second method shutdown VMs (CUCM and SUB-1) and move them then change their  IPs at the second location 

but in this method i will change the IPs of PUB and SUB without network connectivity to the SUB-2, the database will be affected at SUB2

as following the guide i didn't find if changing the IPs require all nodes to be reachable before doing the change or not.

[Roger Kallberg]

All nodes in the cluster need to be connected with each other before you start the process of changing IP. The process for changing IP in CM is outlined in this document. IP Address and Hostname Changes Also this blog post has helped me when doing this before. Change CUCM IP Address Cisco 

[Abdelrhman Elmenyawe]

Hello Roger,

thanks for your response and clarification for doing the change when all nodes of the cluster are connected.

so I will start to change the IP of Pub then restart, change IP of sub1 then restart 

set the new IP of pub on all subscriber nodes,

then when the pub start again with the new IP address, sub2 will not connect to PUB as for now they both have different subnets unitl shutting down the pub and moving it to the next location,  

at that period of time when the pub restart after the change until shutting down, will this be a problem for the datatbase replication?

I believe there will be no issues, as the database replication timeout is default to 5 min, can i increase it before the change to 10 min? and reverse backe to its default after finishing moving the servers

[Roger Kallberg]

You’re overthinking this. The database replication will recover once you have moved the nodes to the new location. You do not need to move it in offline mode if you have vCenter that has access to the source and destination hosts.

[Abdelrhman Elmenyawe]

Thanks Roger  i just want a smooth transition without any problems especially with cucm db so sorry for my questions

Regarding moving, I will move the UCS server that contains the VMs not only VMs