Bridging

Overview

  • Bridging creates a virtual switch
  • A bridge can handle STP (be aware of it!)
  • Usually the bridge uses a physical interface like eth0 as uplink

Setup

  • Install bridge-utils
  • Add a new bridge interface
brctl addbr br0
  • Add uplink
brctl addif br0 eth0
  • Add other ports
  • Show config
brctl show
  • Remember to disable STP if you dont need it!
brctl stp br0 off
  • Switch of network-manager
  • Here how a bridge can be automatically configured with RHEL/CentOS/Fedora
DEVICE=br0
TYPE=Bridge
ONBOOT=yes
DELAY=0
BOOTPROTO=static
IPADDR=192.168.100.1
NETMASK=255.255.255.0
STP=off
  • And how to add eth0 as uplink
BRIDGE=br0
NM_CONTROLLED=no

Firewalling

  • To disable firewalling between bridge ports check /proc/sys/net/bridge/bridge-nf-call-*