Have a request that on one extension(extA) only, to forward all incoming external calls to another extension(extB) and allow only internal calls to ring to extension(extA). I didn't see a way of doing this under the extension itself. Any help would be appreciated. Thanks!
FYI, you need to mention what call control, and version you use to get any assistance, and not just the problem/what you want to do.
Its CUCM 8.6.
I think i figured it out anyway,
I created a Translation Pattern using the DID that wants to forward external calls and set the Called Party Transform Mask to the internal extension i want to accept the external calls.
So basically \1+(DID) -> extension
I was thinking along the same lines for CUCM, if it's only one number, create a TP using the same DN as A, make sure that only the inbound CSS from the GW has access to it, and configure whatever call handling you wanted to happen.
Internal phones should not be able to reach the TP, but the DN directly.