CUCM pub and sub will be temporarily disconnected during Core replace

[jaheshkhan]

We are upgrading our core switches. During this process, the CUCM publisher and subscriber will be temporarily disconnected from the LAN network. Will this affect the CUCM cluster? Do we need to shut down the CUCM cluster servers during this time?

[Roger Kallberg · Accepted solution]

Assuming that your CM publisher and subscriber is in the same IP network it won’t even be noticed by the cluster nodes. That said, you should not need to do anything when changing out your core switches, even if the cluster nodes were in different IP networks. They will reconnect with each other once the network is operational again.

[jaheshkhan]

thank you. we didnt shutdown the servers. it worked properly without any issue.