Our phone system is in an active/passive setup and when we flip between them they send a SIP Re-Invite with a replaces option to the Adtran so that the new active server can take over the call. When we send this to our NetVanta 6410 we get back a 503 Service unavailable. I am trying to figure out how I can set up the NetVanta so that it will take the replaces and send the SIP traffic to the new server. Anyone else been able to set something like this up.
