I have a campus Call Manager solution going in place and want to confirm TFTP server redundancy, or the lack thereof.
Our design has three Call Managers; a publisher/TFTP and two subscribers. I would like to elect one or both of the subscribers as backup TFTP servers. Can the phones support multiple TFTP servers through DHCP config? If not, what are our other options?
Thanks in advance,
SE Manager/Sr. Engineer
Each CallManager in the cluster where Cisco TFTP is installed can be used as a TFTP server by devices.
However, the phones/gateways do not support a list of TFTP servers, they will only ever use the first one listed.
Keep in mind that the only thing you would not be able to do if the TFTP server is unavailable is get new devices to register. Existing devices that have already received their configuration file from the TFTP server will continue to operate normally.
Is this limitation still in place? I'm bringing up another Subscriber and the only way to get a phone on it since it's the only UCM listed in the CMG is to set Alternate TFTP to 'Yes.' I understand this is only for bringing up new instruments in the case the other TFTPs listed aren't available, but wouldn't it make more sense to travers the whole list and not the first two?
Craig L. Pollitt
Yes you can use two TFTP servers for redundancy, read the deatils in the CUCM design guide at the link below, make sure to read the note too. The link is for CUCM ver 6.0 scroll down a bit to read about DHCP and Option 150.