Hi all. I have a question I have been considering. I have a client that wants me to upgrade their callmanager 4.x systems. They have a clusterd envioronment, I think with 4 callmanagers clustered together total. I have every intention of upgrading all 4 of the callmanagers, hopefully as quickly as possible. But, my concern is that I wont get done in one day. So, my questions are these:
1. If, hypothetically, I upgrade two one day, and do the last two say a couple of days later, how will the phones react to this?
2. If phones register partially to the upgraded callmanagers, and partially to the NON-upgraded callmanagers, will the phones registered to the upgraded callnanager be able to call the phones registered to the NON-upgraded callmanager?
3. If #2 is "No, they can not call each other", Im assuming that will mean that they will also not be able to call out to the PSTN or receive calls from the PSTN, correct?
4. If you were in this situation, and given that there may be potential problems between upgraded and NON-upgraded CMs, what would you do to rectify?
Thanks all for the consieration in this.
