CCM Redundancy on phones with cluster

[kdotzoltan_2004]

Hi!

We've just added a subscriber to a CCM installation (CCM 3.3.3, two SPE's in a ICS7750 chasis), without too much hassle. The database is synchronized, phones subscribed to each CCM work, communicate, etc.

My problem is the following: as long as phones (7905Gs and 7960Gs) are set up with a single TFTP sever, they are only aware of a single CallManager, at least only one appears in their CM list. And if that CM (or the connection to it) fails, the phones fail, instead of registering with the secondary CCM.

If a secondary TFTP sevrer is added to their configuration manually, (the sec. TFTP in this case beeing the subscriber server) they see both CallManagers correctly, and register to the secondary unit in case of failure.

What might we have done wrong? How can the phones be "told" that there is a secondary CCM on the network as well (as there are ~150 phones, manual reconfig should be avoided as possible :-) )?

[JeffG1]

I think you need to add the other ccm ip to your DHCP option 150. Then they will both show up...

Also be sure you have added the new CCM in as a server, then a CCMserver and add it to the cluster...

[kdotzoltan_2004]

The phones already have a TFTP server set up, namely the publisher.

I had some partial results, with using XMDefault.cfg.xml, which I could use to send both CCM's to the phones. But: the CCM's TFTP server will erase XMLDefault.cnf.xml after an update to "System/Device Defaults". [In the mean time, I found this confirmed in cisco docs: Cisco's tftp server will "build" cnf.xml files. -- although I didn't succeed in getting a XMLDefault.cnf.xml file from it, when there was none.]

Using an alternative TFTP server works, but I'd like to avoid that, as I'm concerned it might affect adversely CCM functionality (like I don't know if I would be able to manage the aforementioned Device Defaults in this case)

Other question: is there any documentation to be found on XMLDefault.cnf.xml?