Setup VLAN interface on CentOS

There are some scenarios where we want to assign multiple IPs from different VLAN on the same Ethernet card (nic) on Linux servers (CentOS / RHEL). This can be done by enabling VLAN tagged interface.

Let’s assume we have a Linux Server, there we have one Ethernet card (em1).

So attach VLANs 4 tag to NIC em1 using the ip command

ip link add link em1 name vlan4 type vlan id 4

To view the VLAN, issue the following command:

ip -d link show vlan4

Bring up the interface using below ip command:

ip link set dev vlan4 up

Now we can assign the IP address to tagged interface from their respective VLANs using beneath ip command,

ip addr add 172.16.3.188/24 dev vlan4

To delete created VLAN interface use next command

ip link delete dev vlan4@em1

It will work to the next reboot. For saving the configuration edit the network settings stored in directory /etc/sysconfig/network-scripts/.

Additional information

• ip command cheat sheet - For Red Hat Enterprise Linux.
• Configure 802.1q vlan tagging using the command line - Manual from RHEL authors.
• How to Configure VLAN tagged NIC (Ethernet Card) on Linux Servers- Another instruction to configure VLAN on Linux.