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CUCM 11.5 Trust List

Level 4
Level 4

Hi Guys


I´m performing a fresh install to a CUCM 11.5 (the old version of CUCM is 8.6.2). I´m performing a some IP Phone test (firmware download, locale, etc) before updating and I modified the TFTP manually in each telephone to the IP of the new CUCM. I have problems with the Trust List.
- This problem is due to I modified manually the TFTP ?
- This problem is solved using DHCP option 150 with the IP of new CUCM?
- How to check this before the date of migration to CUCM 11.5?


4 Replies 4

Georgios Fotiadis
VIP Alumni
VIP Alumni

Your phones will fail to register to the new CUCM because of the ITL files installed on them. You will have to either manually delete them in the day of migration (not very convenient) or use the "Prepare Cluster for Rollback to pre 8.0" Enterprise Parameter.

This should be helpful to you: CUCM Security By Default and ITL Operation and Troubleshooting

Please rate if you find this helpful.

Understanding how the ITL works is critical to doing this safely. I strongly recommend reading the link Georgios provided.

Having said that, you should not need the rollback parameter or need to manually clear the ITL from the phone. Follow this process so the TVS service on the old cluster trusts the new cluster and allows the phone to update it’s ITL.
Note that the old cluster must be online/reachable when the phone attempts to move over for this to work.

PS- Use DHCP Option 150! Setting TFTP manually is a massive waste of your time.

Dear Jonathan

Thank you for you help.


Thank you for you help.