I have a Mega cluster of 14 CUCM SUB and intend to add 2 more CUCM SUB to the max that Cisco allows. Before I intend to add it into the cluster, I saw there is a bug CSCub12922: "Add new subscriber to existing 8.6+ CUCM cluster cause all device reset" which say all device will be resetted.
I just want to confirm if it refers to all devices(phones, gateways, etc) under this new CMG(Call Manager Group) OR ALL devices in the cluster irregardless of the CMG they are assigned.
Any advice will be much appreciated.
This is documented under the following
Add new subscriber to existing 8.x CUCM cluster cause all device reset
Adding a new subscriber to existing 8.x CUCM cluster cause all device reset due to database update. Issue recreated in lab when "Prepare Cluster for Rollback to pre 8.0" set to both true & false. The symptom and logs are the same in each scenario
This is not a bug. The condition is applicable only to CUCM 8.6 and higher releases. Whenever a node is added to CUCM cluster , from CUCM 8.6 onwards , the phones belonging to that Call Manager group will be automatically restarted
These resets are soft reset, which means that if the phones are having an active call they will not get reset at that moment. This will only reset devices that are idle.
Sadly "After you install a new node in an existing cluster, all phones that are registered to the cluster are reset."
This is documented here
According to what was posted above,