Are you sure you factor reset the phone using the method mentioned in document.
can you also get the following for us along with pcap after factory reset as Jamie mentioned?
tftp -i tftpserveripaddress get SEP<macaddress>.cnf.xml
That's the thing, the phones have the right config, you can see that, however, they're not registering to the server. A phone would only use a secondary server if it cannot communicate with the primary server as it's not sending an ACK to the keepalive the phone is sending.
You said db replication is OK, and that's usually one of the things that can cause this.
Aside from some sort of network issue, I could only think of some FW problem, and that's as easy as trying a few different FWs on those phones and see what happens. If you're not running the latest phone FW for the 7940, try upgrading it.
I am having the same issue, however I noticed when accessing the phone's url - the TFTP server is pointing to the Publisher...can this potentially be the cause?
Any feedback will be greatly appreciated!!
If you go to one of those phones that didn't move to the SUB, do you see both servers listed in the CUCM group in the phone itself??
Or you can try to download the .cnf.xml from the phone to confirm if the CUCM group does have both servers??
If it doesn't you might want to rebuild all the TFTP config files.
Thanks for the suggestion. I'll be visiting the customer again on Sunday only. Meantime can you please tell me how to rebuild the TFTP config files?
OK, you can also see that if the web access is enabled on the device in their webpage, it will list the CUCM servers it has in the config.
To recreate the config files, go to the TFTP service parameters, click advanced and change build CNF files to Build All, then restart the TFTP service and reset the devices.
Did you check the device pool configuration for the phone? What is the Cisco Unified CM Group set for? It should have the subscriber listed first and then the publisher (or secondary subscriber if you have more than one on the cluster).
I know this post is old but did you ever find a resolution to this issue? I'm experiencing the same issue except with 7960s (which is just a 6 line 7940). All other phone models will register with the Subscriber fine, except 7960s. Any help would be appreciated.
In my case the root cause was that the IP address of the one of the subscribers was changed at some point. The server's 'name' (found by going to System>Cisco Unified CM) was configured to the original IP so they didn't match.
You can also check this by going to the CLI and running the command "show ctl" and look for the "DNSNAME" field.
I found this by going to the 7960 and attempting to hard code an Alternate TFTP server to the one that it wouldn't register to....whenever I attempted to save it it threw the error "TFTP not in CTL". So essentially the 7960s wouldn't trust the CTL since the "DNS Name" didn't match.