I've got two 3845 voice gateways each configured the same. The IOS version is 12.4(13f). In slot 0 I have 4 PVDM2-64 modules. In slot 1 I have an NM-HDV2-2T1/E1 with 3 PVDM2-64s. Slots 2, 3 and 4 all have NM-HDV2-2T1/E1 modules and none have any onboard PVDMs. Hardware conferencing is configured.
I have 2 questions:
1) Is it possible to share the DSPs from some of the other boards so I can use Slots 2, 3, and 4 without having to physically move the PVDMs? If I put "dspfarm" under voice-card 3, I can get signaling, but no audio. Phone rings, caller ID shows up, but you can't hear anything in either direction. I set up another ISR directly connected with a T1 crossover and got the same result, so it's not an issue with ACLs.
2) If I have 3,000 phones that will be using these ports to connect to the PSTN. Is it likely that I'll need more PVDMs anyway? Remember there are 2 VGWs here so the load for each router is divided in half. I've had conflicting answers to this question. Is there a good rule of thumb? A web link with a definitive answer?
I've attached what I think are important configs, but the basic issue is what's described above.