I upgraded cucm to 8.5 and used the bridge upgrade , and successfully restored and all the other phone types are registered and working fine except the cisco 9971 phone
i think it is the issue with the itl certicate from the tftp
and the tftp is also not accessible i can't download any file from the tftp through sftp of cli
please need help.
You mentioned bridged upgrade. Have you moved to newer hardware or are you still on the hardware only supported in bridged fashion?
There was defect ID CSCtn50405 where the certificate private keys were not backed up by DRS and would break ITL trust post-upgrade. If the version you took the backup from is not fixed there is a workaround: Get TAC to root into the box and manually export the certificate private keys. They can then manually upload those to the new box and restart services. When I had to go through this the only people who knew how were the DEs in India.
Lastly, the 8900/9900 series phones do not download firmware through TFTP. They use HTTP over port 6970. This means that tomcat must be running.