Use the set mgc list command to set Branch Gateway MGC. You can enter the IP addresses of up to four MGCs with the set mgc list command. The first MGC on the list is the primary MGC. Branch Gateway searches for the primary MGC first. If Branch Gateway cannot connect to the primary MGC, it searches for the next available MGC on the list. If the gateway is configured with IPv4 (PMI) and IPv6 (PMI6) addresses, you can set IPv4 and IPv6 addresses in the same index on the MGC list. Gateway first uses the IPv4 address when it tries to register to Communication Manager.