Jump to 9 - phones at moment of switch-over (is a reboot needed?)

[kasper123]

We are doing a jump upgrade from 7.1.5 to 9.1 and are ready for the switch-over.

As a preparation we have already upgraded all the phones to the firmware that comes with CUCM 9.1.

Can anyone tell me what will happen with the phones at the moment of the switchover?

Will they automaticaly connect to the new cluster, will they reboot or do they have to be manualy rebooted?

The phones and computers attached to them are used 24/7 so there really isn't a convenient window for upgrade and we need to plan this in advance.

Regards.

[Manish Prasad]

If you have already done phone firmware upgrade and you can see upgraded firmware on physical phone then you don't need to reboot/reset phone individually. Just replace TFTP server ip from DHCP option and they will register with the cluster.

Sent from Cisco Technical Support iPhone App

[Joseph Martini]

Assuming no IP addresses are changed in the CUCM cluster, the only thing that will happen when the switchover happens is that the TCP socket will close and the phone will open a new one once the new servers are reachable.  Depending on how long the switchover takes the phones may show unregistered from the time the old servers are taken down, and the new ones made available, but the phones do not have to be reset and will not reboot.  If you are simply shutting down some switchports and enabling other ports to swap the cluster, the phones should just flicker for a second as they re-register.

Just make sure that the ARP entries are cleared/updated when doing this.  The switchover may take a little longer if a network device has to wait for the ARP cache to time out before the new servers are reachable.  The default ARP cache timer on the 79XX phones is 40 minutes unless a different value is learned via DHCP options.  This timer would only effect your environment if the phones are on the same broadcast domain as the servers.