And saw the requirement to Utilize the "Prepare Cluster for Rollback to pre 8.0" Feature
AND to NOT edit certificates on both TFTP servers at the same time. This gives the phones no TFTP server to trust and requires the local administrator to manually remove the ITL from all phones.
Obviously, using the Multi-SAN feature, prevents us from applying the certs to the TFTP nodes individually, so I am a little concerned.
I just spoke with TAC who stated that we no longer need to use the rollback feature and we do not need to make changes to the TFTP nodes individually anymore. While I do believe him, I am hoping to get the advice from anybody who has updated these certs recently and can confirm both of these things to be true.
We are a hospital the relies heavily on Extension Mobility for all of our Call Centers, and breaking these services would essentially be catastrophic. Any advice is greatly appreciated!