Prepare Cluster for Rollback to Pre-8.0
When migrating IP Phones from clusters from 8.X on wards to 9.X /10.X /11.X versions, you may encounter issue with security files i.e., ITL files (Initial Trust List). which is a new security feature by default. The ITL files needs to be deleted either manually or automatically in order to register to the target Cisco Unified Communications Manager version. If the ITL files are not deleted, the device may fail to register to the new cluster.
There is a feature which was introduced in 8.X version “Prepare Cluster for Rollback to Pre-8.0”. This feature is located in Enterprise Parameters. If you are doing a flash cut-over i.e., migrating all the cluster IP Phones at one go from Legacy Cluster to New Cluster, then this feature is most appropriate and useful. It will help you to register your IP Phones from legacy 8.X Cluster to New Clusters without issues. If you are migrating the IP Phones per site/location basis, this is not a recommended option.
How to deal with this feature if you are migrating all the IP Phones at one go from Legacy Cluster to New Cluster?
Configuration in Legacy CUCM Cluster:
- Login to Legacy Cluster CUCM >
- Go to Enterprise Parameters > Prepare Cluster for Rollback to pre 8.0 > Set the parameter to True
- Now the IP Phones will be rebooted and the dependency of ITL files will be removed
- IP Phones will re-register to the Old Cluster
Configuration in Legacy CUCM Cluster and Switch:
- Login to the New Cluster CUCM >
- Go to Enterprise Parameters > Prepare Cluster for Rollback to pre 8.0 > Set the parameter to True
- Change DHCP option 150 and ensure you put the new cluster TFTP IP Address.
- Reset the IP Phones or Device Pool from the Legacy Cluster
Monitoring the IP Phones registration :
- The IP Phones should start registering to the New Cluster. Monitor and ensure that all the IP Phones are registered. You may use RTMT to monitor the IP Phones registration process.
- On the New Cluster > Go to Enterprise Parameters > Prepare Cluster for Rollback to pre 8.0 > Set the parameter to False
- The IP Phones should start re-registering to the New Cluster again. Monitor and ensure that all the IP Phones are registered.
Hope this helps!!
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