We have a client (that is rapidly growing) that is out of licenses and voicemail quota space on one UC500 which is connected to a SIP circuit. I have setup a second UC500 internally on their network that they are borrowing until they can get a second location purchased to move some of their employees too. I have been successfully in internal calling to work between the 2 UC500s, but cannot get external calls from the internal UC500 through the Main UC500 out the SIP trunk.
When looking at the debugs with TAC, it shows the main uc500 accepting the call from the internal UC500 and then establishing the connection over the SIP trunk. The SIP server authenticates correctly, but then the call is disconnected and the SIP server. The TAC engineer stated that this could be a problem with the carrier (CBeyond). I contacted them and they stated that the initial connection and INVITE is heard and accepted by their SIP server, but when the SIP server tries to send an INVITE back it is denied or ignored from the main UC500 and then the call is dropped.
Is there any way to allow this to work, or is this type of setup not possible?