We are going add another SIP provider and use a new public IP to connect to it, but we do not have enough physical interfaces. I tried to add a sub-interface on Linux, I can see it is displayed when I use command “ifconfig”, but I can not see it in the SBC web portal. So, how can configure two IPs by using one physical interface in SBC?
You could create two IP interfaces on one physical interface by using virtual port and VLAN. So, you create the virtual port on that physical interface, then create two VLANs, one untagged and one tagged, and on these two VLANs, assign IP interfaces. Please see below,