Setting up a network alias is basically using multiple ip´s on one NIC interface or Lan Card.
This is useful if you are hosting multiple websites that uses certificate residing on only one server.
Note the ip? should be on the same subnet for it to work.
lets sat eth0 is configured with IP number 10.10.10.2
to configure eth0:0 alias
sudo as root # /sbin/ifconfig eth0:0 10.10.10.3 up
to verify that it is running # /sbin/ifconfig -a
or ping 10.10.10.3 this is not permanent so if you reboot your changes will be gone.
to make it permanent you need to go to # cd /etc/sysconfig/network-scripts/
you need to copy ifcfg-eth0 and create ifcfg-eth0:0
to do that # cp /etc/sysconfig/network-scripts/ifcfg-eth0 /etc/sysconfig/network-scripts/ifcfg-eth0:0
then # nano /etc/sysconfig/network-scripts/eth0:0 change the assigned IP and set ONBOOT=YES
so if your eth0 is:
# Intel Corporation 82566DM-2 Gigabit Network Connection
DEVICE=eth0
BOOTPROTO=none
HWADDR=00:1c:c0:ad:86:e5
ONBOOT=yes
NETMASK=255.255.255.0
IPADDR=10.10.10.2
GATEWAY=10.10.10.1
TYPE=Ethernet
then eth0:0 will be:
# Intel Corporation 82566DM-2 Gigabit Network Connection
DEVICE=eth0
BOOTPROTO=none
HWADDR=00:1c:c0:ad:86:e5
ONBOOT=yes
NETMASK=255.255.255.0
IPADDR=10.10.10.3
GATEWAY=10.10.10.1
TYPE=Ethernet
