nic alias

configure a network interface and alias. For example:

eth0 NIC IP - 192.168.1.5
eth0:0 first NIC alias: 192.168.1.6

To setup eth0:0 alias type the following command as the root user:

# ifconfig eth0:0 192.168.1.6 up

Verify alias is up and running using following command:

# ifconfig -a
# ping 192.168.1.6

However if you reboot system you will lost your alias. To make it permanent you need to add it network configuration file:

If you are using Debian Linux
Open the file /etc/network/interfaces:

# vi /etc/network/interfaces

Append text as follows:

auto eth0:1
iface eth0:1 inet static
name Ethernet alias LAN card
address 192.168.1.7
netmask 255.255.255.0
broadcast 192.168.1.255
network 192.168.1.0

Save the file and restart the network:

# /etc/init.d/networking restart

If you are using Red Hat / Fedora Linux
Copy etc/sysconfig/network-scripts/ifcfg-eth0 file etc/sysconfig/network-scripts/ifcfg-eth0:0 -

# cp /etc/sysconfig/network-scripts/ifcfg-eth0 /etc/sysconfig/network-scripts/ifcfg-eth0:0

Open file /etc/sysconfig/network-scripts/ifcfg-eth0:0 using vi text editor:

# vi /etc/sysconfig/network-scripts/ifcfg-eth0:0

Find entry that read as follows:

DEVICE=eth0

Replace with:

DEVICE=eth0:0

Find entry that read as follows:

IPADDR=xxx.xxx.xxx.xxx

Replace it with your actual IP address:

IPADDR=192.168.1.7

At the end your file should like as follows:

DEVICE=eth0:0
IPADDR=192.168.1.7
NETMASK=255.255.255.0
NETWORK=192.168.1.0
ONBOOT=yes
NAME=eth0:0

Open file /etc/sysconfig/network-scripts/ifcfg-eth0 and make sure file does not have a GATEWAY= entry:

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

Find the entry that read as follows:

GATEWAY=192.168.1.254

Remove or comment it out by prefixing # (hash) :

# GATEWAY=192.168.1.254

Save the file. Add the GATEWAY= to your /etc/sysconfig/network:

# vi /etc/sysconfig/network

Append or modify GATEWAY entry:

GATEWAY=192.168.1.254

Save the file. Reboot the system or run the following command:

# ifup eth0:0

OR

# service network restart