Setup bridge device on CentOS

Posted on Tue 19 April 2011 in misc

Howto setup a bridge device on CentOS or Fedora.

If you need to bring your KVM VM's into the same local area network like your host is in you need to configure a bridge device.

  1. Install all needed packages:

    yum install bridge-utils

    yum install tunctl

  2. Disable NetworkManager and enable network at boot time:

    chkconfig NetworkManager off

    chkconfig --levels 35 network on

    /etc/init.d/NetworkManager stop

    /etc/init.d/network restart

  3. Create br0 configuration

    vi /etc/sysconfig/network-scripts/ifcfg-br0

Change following configuration to your needs.

DEVICE=br0
TYPE=Bridge
BOOTPROTO=static
DNS1=192.168.0.1
GATEWAY=192.168.0.1
IPADDR=192.168.0.100
NETMASK=255.255.255.0
ONBOOT=yes
SEARCH="example.com"

  1. Modify eth0 configuration:

    vi /etc/sysconfig/network-scripts/ifcfg-eth0

    DEVICE=eth0
    HWADDR=00:1e:90:f3:f0:02
    ONBOOT=yes
    TYPE=Ethernet
    IPV6INIT=no
    USERCTL=no
    BRIDGE=br0

5. Restart network or reboot machine to see if everything is configured persistent

/etc/init.d/network restart

or

reboot

Here are some additional information on the libvirt page. If you have performance problems with your bridge device you maybe need to disable the netfilter on the bridge interface.

CentOS KVM