CentOS 6.2 network card Settings

The following mainly introduces the detailed steps of network card binding under CentOS6.2 using bonding which comes with the system.

Note: please turn off the NetworkManager service before configuring
[root@h63 ~]# service NetworkManager status && service NetworkManager start
Network card binding can bind multiple network CARDS once, you can use ifconfig-a to view your network card information, such as:
[root@h63 ~]# ifconfig -a

em1             Link encap:Ethernet   HWaddr 78:2B:CB:30:08:03
                  UP BROADCAST RUNNING SLAVE MULTICAST   MTU:1500   Metric:1
                  RX packets:48236002 errors:0 dropped:0 overruns:0 frame:0
                  TX packets:16156472 errors:0 dropped:0 overruns:0 carrier:0
                  collisions:0 txqueuelen:1000
                  RX bytes:4838973371 (4.5 GiB)   TX bytes:1301118550 (1.2 GiB)
                  Interrupt:36 Memory:d6000000-d6012800

em2             Link encap:Ethernet   HWaddr 78:2B:CB:30:08:05
                  UP BROADCAST RUNNING SLAVE MULTICAST   MTU:1500   Metric:1
                  RX packets:42385720 errors:0 dropped:0 overruns:0 frame:0
                  TX packets:7283526 errors:0 dropped:0 overruns:0 carrier:0
                  collisions:0 txqueuelen:1000
                  RX bytes:4307780986 (4.0 GiB)   TX bytes:466840625 (445.2 MiB)
                  Interrupt:48 Memory:d8000000-d8012800

em3             Link encap:Ethernet   HWaddr 78:2B:CB:30:08:07
                  BROADCAST MULTICAST   MTU:1500   Metric:1
                  RX packets:0 errors:0 dropped:0 overruns:0 frame:0
                  TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
                  collisions:0 txqueuelen:1000
                  RX bytes:0 (0.0 b)   TX bytes:0 (0.0 b)
                  Interrupt:32 Memory:da000000-da012800

em4             Link encap:Ethernet   HWaddr 78:2B:CB:30:08:09  
                  BROADCAST MULTICAST   MTU:1500   Metric:1
                  RX packets:0 errors:0 dropped:0 overruns:0 frame:0
                  TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
                  collisions:0 txqueuelen:1000
                  RX bytes:0 (0.0 b)   TX bytes:0 (0.0 b)
                  Interrupt:42 Memory:dc000000-dc012800

There are four network CARDS, em1, em2, em3 and em4, respectively. We make a binding between em1 and em2, and the binding mode is 6 (for the introduction of network card binding mode, please see the analysis of Linux network card binding). First, I give the device after network card binding a name bond0 (the name can be customized), and create:
[root@h63 ~]# vim /etc/sysconfig/network-scripts/ifcfg-bond0
DEVICE=bond0# device name
Static IP BOOTPROTO = static #
ONBOOT=yes   # starts automatically
IPADDR=172.16.16.63# device bound IP
GATEWAY=172.16.23.254             # device binding gateway
NETMASK=255.255.248.0 # mask for device binding
TYPE=Ethernet # type of device binding

Edit the network card that needs to be bound:
[root@h63 ~]# vim /etc/sysconfig/network-scripts/ifcfg-em1

DEVICE=em1
BOOTPROTO=none
ONBOOT=yes
Name of device after MASTER=bond0# binding
SLAVE=yes
TYPE=Ethernet

[root@h63 ~]# vim /etc/sysconfig/network-scripts/ifcfg-em2

DEVICE=em2
BOOTPROTO=none
ONBOOT=yes
MASTER=bond0# device name after binding
SLAVE=yes
TYPE=Ethernet
Note: do not fill in IP address and MAC address when configuring the network card

Configure load mode Settings:
[root@h63 ~]# vim /etc/modprobe.conf

alias bond0 bonding
options bond0 miimon=100 mode=6

Note: mode is the network card binding mode, here is mode 6

Can also be in the/etc/modprobe d/create a file:
[root@h63 ~]# vim /etc/modprobe.d/bond

alias bond0 bonding
options bond0 miimon=100 mode=6

Bind configuration complete, restart the network service
[root@h63 ~]#service network restart

View the network card binding:

[root@h63 ~]# cat /proc/net/bonding/bond0
Ethernet Channel Bonding Driver: v3.6.0 (September 26, 2009)

Bonding Mode: adaptive load balancing
Primary Slave: None
Currently Active Slave: em1
MII Status: up
MII Polling Interval (ms): 100
Up Delay (ms): 0
Down Delay (ms): 0

Slave Interface: em1
MII Status: up
Speed: 1000 Mbps
Duplex: full
Link Failure Count: 0
Permanent HW addr: 78:2b:cb:30:08:03
Slave queue ID: 0

Slave Interface: em2
MII Status: up
Speed: 1000 Mbps
Duplex: full
Link Failure Count: 0
Permanent HW addr: 78:2b:cb:30:08:05
Slave queue ID: 0

At this point, the network card binding is complete. If there is anything wrong, please advise.