Bridges

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Introduction

A bridge works like a transparent switch/hub between two or more interfaces and clients on any of the bridged interfaces can communicate with each other exactly as if they are part of the same network.

Example

Below is a complete example in plain-text for bridging two local interfaces with each other and clients on either side of the bridge sharing the same DHCP Server and firewall rules. Pay particular attention to the fact that the vr2 interface does not have any IP address assigned to it. For bridging two interfaces in two geographically separate locations over a tunnel see the article on EtherIP.

firewall {
	pass quick on lan label LAN
	pass in log quick on mgmt proto tcp to (mgmt) port {$mgmt_ports} label management
	match out on wan inet nat-to (wan:0) label NAT
	pass out quick on wan label outbound
}
interface bridge0 {
	firewall {
		skip
	}
	member vr1
	member vr2
}
interface vr0 {
	description "Internet"
	group "wan"
	dhcp-client
}
interface vr1 {
	description "LAN"
	group "lan"
	group "mgmt"
	address 192.168.1.1/24
	dhcp-server {
	}
}
interface vr2 {
	group "lan"
	group "mgmt"
}
system {
	authentication {
		user "admin" {
			password "admin"
		}
	}
	dns {
		name-server 8.8.8.8
	}
	http-server
	ssh-server
}