Hi,
I'm doing migration from CUCM 6.1 to 9.1. The existing phone running on firmware e.g 7911 SCCP11.8-5-3SR1S while CUCM 9.1 using SCCP11.9-3-1SR1-1S.
I need to upgrade the phone firmware at CUCM 6.1 first before proceed to swing over to CUCM 9.1 a few days after that. So it will take less downtime to the IP Phones once registered to CUCM 9.1.
Can i just straight away upload the firmware and restart the TFTP? Any dependancy (device pack, upgrade path etc) besides the new phone firmware itself for my case?
Thanks