How to add multiple IP addresses to a NIC in Linux network configuration

Tangxiang Daily-March 16, 2017:

How to add multiple IP addresses to a NIC in Linux network configuration

There are two common ways that Linux systems configure VIPs for network cards: alias IP, and secondary IP

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Aliases IP (alias IP)

The IP alias is created and maintained by the Ifconfig command of the Linux system, and the alias IP is the second and higher IP that is bound on the NIC device.

Description: The configuration of the alias IP will be abandoned in the future Linux system, because there will be no more ifconfig commands in the future system.

①. Methods for manually configuring aliases for VIPs

Ifconfig eth0:1 10.0.0.100 netmask 255.255.255.224 up

Route add-host 10.0.0.100 Dev eth0---Add a host route, optional configuration

Description: The IP alias configuration is temporary and will be lost once the NIC is restarted

②. How to Manually view VIP aliases

Ifconfig

③. How to manually delete an alias VIP

Ifconfig eth0:1 10.0.0.100 netmask 255.255.255.224 down

Ifconfig eth0:1 Down

④. Method for permanent alias IP

Write to the network card profile to make the alias IP permanent, the name can be ifcfg-eth0:x,x 0-255 of any number, IP and other content formats and Ifcfg-eth0 consistent

Vim/etc/sysconfig/network-scripts/ifcfg-eth0:1

Device=eth0:1

ipaddr=10.0.0.100

Secondary IP (secondary IP address)

The secondary IP is created and maintained by the IP command of the Linux system, and the IP addr add is created as a secondary IP and cannot be viewed through ifconfig.

But the alias IP created by Ifconfig can be viewed in the IP addr Show command

Description: Need to focus on the master ※

①. Methods for manually configuring aliases for VIPs

IP addr Add 10.0.0.100/24 dev eth0

IP addr Add 10.0.0.101/24 broadcast 10.0.0.255 dev eth0

IP addr Add 10.0.0.101/24 broadcast 10.0.0.255 dev eth0 label eth0:0

②. How to Manually view VIP aliases

IP addr

③. How to manually delete an alias VIP

IP addr del 10.0.0.100/24 dev eth0

IP addr del 10.0.0.101/24 broadcast 10.0.0.255 Dev eth0

VIP Configuration Summary:

1. heartbeat2.1.4 and previously used alias ip,heartbeat2.1.4 later use is the secondary IP, provide VIP services

2. Keepalived has always been used as an auxiliary IP service

How to add multiple IP addresses to a NIC in Linux network configuration