====== Add an ethernet subinterface ======

**Probably obsolete with the rise of [[linux:ubuntu1804netplan|Netplan]]**

Assuming RedHat, Centos or Fedora.

The process:
Go to the directory with the networking scripts

  cd /etc/sysconfig/network-scripts

Copy the original network script for the interface

  cp ifcfg-eth0 ifcfg-eth0:1

Edit ifcfg-eth0:1 and change the device name, change DEVICE=eth0 to DEVICE=eth0:1
Change the IP address, change IPADDR=[current value] to IPADDR=[ip address for subinterface]

Save the file. \\
Restart the network service. \\

  service network restart


Check with ifconfig.