Bridge without adding interfaces?

It sounds like maybe you are thinking of bridging but actually want to do routing, perhaps combined with NAT.

Sorry I expressed myself in a wrong way. I do not want to deploy XG firewall in "Bridge mode", but I want to only create virtual interface on XG firewall in "Standard mode" (Routing/NATting).

What do you mean by "virtual interface" ?

Do you mean a VLAN?

I think you want to spell out the use case in a bit more detail. I wasn't talking about bridge mode -- i.e. turning off routing -- but rather the ability to bridge interfaces. But it sounds like you're not wanting to bridge two interfaces into one, but to route a subset of traffic between two interfaces. Details of the use case -- even better a diagram with addresses/networks -- would help.

I mean L2 "virtual Interface" such as Bridge interface on Mikrotik router. You can create a bridge interface on the Mikrotik without need adding any interface to it.

Hi,

what you appear to be asking about is the use of VLANs? Yes, you can create VLANs on existing XG physical interfaces.

Ian

Hi,

no, I don't want to create any VLANs on physical ports, but create THIS on XG Sophos Firewall...

It would have been nice to describe this from the beginning -- your actual use case, not how you think you should create it.

So they are creating a loopback in a Microtik router. What task do you want to use a loopback interface for?

I don't need create exactly loopback interface, but interface for this use:

1. I have XG firewall with two WAN interface with /31 subnet for P2P connection to Internet.
2. These connections are intended for BGP routing.
3. Over these two WAN interfaces is passed public /27 subnet.
4. I need to establish this public /27 subnet to some "virtual interface". Not on physical interface. Ideally in the WAN zone.

How do I do it?

If we call your two /31 WAN interfaces WAN31A and WAN31B, and the interface you want as WAN27, you're wanting to create WAN27 as a gateway for your user traffic? Do you need WAN27 to be an interface/gateway for reasons other than routing your user traffic through it by default? Doesn't this boil down to routing non-LAN, non-WAN31A/B traffic to WAN27? (I'm just asking clarifying questions here so that someone with more knowledge of multiple-gateways can help you. BGP and three WAN interfaces is beyond my level.)