Binding multiple IP addresses to an NIC in Linux and sharing a single IP address with multiple NICs

Article title: binding multiple IP addresses to an NIC in Linux to share a single IP address with multiple NICs. Linux is a technology channel of the IT lab in China. Some basic categories, such as desktop applications, Linux system management, kernel research, embedded systems, and open-source systems, sometimes need to bind multiple IP addresses to one Nic in Linux. This article introduces the Redhat series (redhat, fedora Core, Centos) and a method that is widely used in Gentoo and other Linux systems.
　
1. how to bind multiple IP addresses to a single Nic in the Redhat series
　
Suppose the NIC that needs to bind multiple IP addresses is eth0, please create a file named ifcfg-eth0: 0 in the/etc/sysconfig/network-scripts directory,
　
Content example:
　

DEVICE = "eth0: 0 ″ IPADDR = "192.168.0.2 ″ BROADCAST = "172.160.255 ″ NETMASK = "255.255.255.0 ″ ONBOOT = "yes"

　
DEVICE indicates the DEVICE name, IPADDR indicates the IP address of the DEVICE, BROADCAST indicates the BROADCAST address, NETMASK indicates the subnet mask, and ONBOOT indicates automatic start at system startup.
　
If you need to bind another IP address, you only need to add the file name to the eth0: x of the DEVICE in the file.
　
LINUX supports up to 255 IP aliases
　
2. it is widely used to bind multiple IP addresses to a single NIC.
　
Ifconfig eth0: 1 192.168.0.3 broadcast 192.168.0.255 netmask 255.255.255.0
　
You can add the preceding command to the self-running startup file. under Gentoo, it is/etc/conf. d/local. start, while some versions of Linux are/etc/rc. d/rc. local.
　
3. how to share a single IP address with multiple NICs
　
You can use multiple NICs to create a network card with the same IP address. This technology actually exists in sun and cisco, respectively known as Trunking and etherchannel technology. in linux, this technology is called bonding. because bonding is included in kernel 2.4.x, you only need to select Bonding driver support in network device options during compilation.
　
Then, recompile the core, restart the computer, and execute the following command:
　

Ismod bonding Ifconfig eth0 down Ifconfig eth1 down Ifconfig bond0 ipaddress Ifenslave bond0 eth0 Ifenslave bond0 eth1

　
Now the two NICs work like one, which can improve data transmission between cluster nodes.
　
You 'd better write these statements as a script, and then use/etc/rc. d/rc. local or/etc/conf. d/local. start is called to take effect on the server.
　
Bonding is a good choice for servers. when there is no Gigabit Nic, using two or three 100 m NICs as bonding can greatly increase the bandwidth between servers and switches. However, you need to set the two ports mapped to the same virtual interface on the vSwitch to connect to the bonding Nic.