You can put a PC in the same subnet and trace from your PC to the phone. Or you can do a extended traceroute from the default gateway (router) of the first 7940 and specify the source ip address as the ip address of the interface on the router that is connected to the first 7940. (possibly through a L2 switch)
To verify the signaling path, you can just ping each phone from the CM.
The media path is a bit tricker. If you have not separated data and voice VLANs, you can plug a laptop into the switch port for one of the phones and ping the other phone. If you have separated voice VLANs, you would need to set the access vlan to be the same as the voice vlan, then ping across.
Now, firewalls or ACLs may still be an issue. But it's not clear what problem you are trying to address.
Well, it depends on your model. If you are talking about phones within a single cluster, the signaling path will have the originating phone's active CallManager involved in all signaling messages to both phones, like this:
(this would be the case even if both phones are registered to different CMs in the same cluster)
However, if you are talking about phones registered to two different clusters, then you will have two CallManagers in the signaling path, like this:
I have 2 seperate clusters. The CM default route is current pointing to the DATA VLAN and from that VLAN, if I do a trace route, the route goes across the data lines. The phone has a default gateway of the Trunk, so can I assume, the phone is sending its calls across the trunk?
Not necessarily. Once you are certain of full IP routability, then you need to double-check your dial-plan. Install/Run DNA and type in the number you want to dial and ensure it hits your trunk in both directions.
Are you getting this error “Installer User Interface Mode Not Supported. The installer cannot run in this UI mode. To specify the interface mode, use the -i command-line option, followed by the UI mode identifier. The value UI mode identifiers...
The below trick might come handy when you have to add a new node to a cluster but you don't have or is unsure of the security password for the publisher. This procedure has been around for ages.
1) Login into the CLI of the Publisher.