Prepare the hardware and OS

Install VLAN Module

• We need to install the VLAN module to run VLANs on the server.

#Install the VLAN package
sudo apt-get update
sudo apt-get install vlan
#Permanently load the module during boot time
sudo su -c 'echo "8021q" >> /etc/modules'
#Reboot the server
sudo reboot
#Confirm that it is loaded
lsmod  | grep 8021q

Install Bridge Utilities

• We need to install the bridge utilities to use the bridging capabilities on the server.

#Install the bridge-utils package
sudo apt-get update
sudo apt-get install bridge-utils

Configure the Interfaces

• If your server has only one interface card, edit the /etc/rc.local file to contain the following:

rc.local

#!/bin/bash
 
#Set up the dummy interface
/sbin/modprobe dummy
/sbin/ip link add dummy0 type dummy
/sbin/ip link set name eth1 dev dummy0
/sbin/ip link set dev eth1 address 00:22:22:ff:ff:ff
/sbin/ip link set eth1 up promisc on
 
#Now add the VLAN
/sbin/ip link add link eth1 name eth1.101 type vlan id 101
/sbin/ip link set eth1.101 up promisc on
/sbin/brctl addbr br0.101
/sbin/brctl addif br0.101 eth1.101
/sbin/ip addr add 10.101.0.1/16 dev br0.101
/sbin/ip link set dev br0.101 up
 
/sbin/ip link add link eth1 name eth1.102 type vlan id 102
/sbin/ip link set eth1.102 up promisc on
/sbin/brctl addbr br0.102
/sbin/brctl addif br0.102 eth1.102
/sbin/ip addr add 10.102.0.1/16 dev br0.102
/sbin/ip link set dev br0.102 up
 
/sbin/ip link add link eth1 name eth1.103 type vlan id 103
/sbin/ip link set eth1.103 up promisc on
/sbin/brctl addbr br0.103
/sbin/brctl addif br0.103 eth1.103
/sbin/ip addr add 10.103.0.1/16 dev br0.103
/sbin/ip link set dev br0.103 up
 
exit 0

• If your server has two or more physical interfaces we do on need to first define a dummy interface.

rc.local

#!/bin/bash
 
#Now add the VLAN
/sbin/ip link add link eth1 name eth1.101 type vlan id 101
/sbin/ip link set eth1.101 up promisc on
/sbin/brctl addbr br0.101
/sbin/brctl addif br0.101 eth1.101
/sbin/ip addr add 10.101.0.1/16 dev br0.101
/sbin/ip link set dev br0.101 up
 
/sbin/ip link add link eth1 name eth1.102 type vlan id 102
/sbin/ip link set eth1.102 up promisc on
/sbin/brctl addbr br0.102
/sbin/brctl addif br0.102 eth1.102
/sbin/ip addr add 10.102.0.1/16 dev br0.102
/sbin/ip link set dev br0.102 up
 
/sbin/ip link add link eth1 name eth1.103 type vlan id 103
/sbin/ip link set eth1.103 up promisc on
/sbin/brctl addbr br0.103
/sbin/brctl addif br0.103 eth1.103
/sbin/ip addr add 10.103.0.1/16 dev br0.103
/sbin/ip link set dev br0.103 up
 
exit 0

Add a Systemd Service for rc.local

• Ubuntu changed the startup system in the more recent releases to Systemd.
• In order for the rc.local file to be run during startup under Systemd, we need a couple of extra steps
• Create the file /etc/systemd/system/rc-local.service with the following content:

# /etc/systemd/system/rc-local.service
[Unit]
 Description=/etc/rc.local Compatibility
 ConditionPathExists=/etc/rc.local
 
[Service]
 Type=forking
 ExecStart=/etc/rc.local start
 TimeoutSec=0
 StandardOutput=tty
 RemainAfterExit=yes
 SysVStartPriority=99
 
[Install]
 WantedBy=multi-user.target

• Then

sudo touch /etc/rc.local
sudo chmod +x /etc/rc.local
sudo systemctl enable rc-local

• Check with

sudo systemctl start rc-local.service
sudo systemctl status rc-local.service

Confirm it is correct

• Reboot the server and confirm that it came up with these bridges configured.

#Issue the **ip a** command to confirm the br0.101, br0.102 and br0.103 are up and has the correct IP Address.
#Also use the brctl command to show you the bridges present
system@rd:~$ brctl show
bridge name	bridge id		STP enabled	interfaces
br0.101		8000.000c294aafdf	no		eth0.101
br0.102		8000.000c294aafdf	no		eth0.102
br0.103		8000.000c294aafdf	no		eth0.103