1.服务器更换网卡（服务器开机网卡的灯是不亮的）
2.进系统进行网卡配置
[root@bj ~]# cat /etc/udev/rules.d/70-persistent-net.rules # This file was automatically generated by the /lib/udev/write_net_rules # program, run by the persistent-net-generator.rules rules file. # # You can modify it, as long as you keep each rule on a single # line, and change only the value of the NAME= key. # PCI device 0x8086:0x1521 (igb) SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="00:1e:67:38:9b:23", ATTR{type}=="1", KERNEL=="eth*", NAME="eth2" # PCI device 0x8086:0x1521 (igb) SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="00:1e:67:38:9b:22", ATTR{type}=="1", KERNEL=="eth*", NAME="eth1" # PCI device 0x8086:0x1521 (igb) SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="00:1e:67:38:9b:21", ATTR{type}=="1", KERNEL=="eth*", NAME="eth0" # PCI device 0x8086:0x1521 (igb) SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="00:1e:67:38:9b:24", ATTR{type}=="1", KERNEL=="eth*", NAME="eth3" # PCI device 0x14e4:0x168e (bnx2x) #SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="00:0a:f7:5c:7a:50", ATTR{type}=="1", KERNEL=="eth*", NAME="eth4"（这是旧网卡的信息） # PCI device 0x14e4:0x168e (bnx2x) #SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="00:0a:f7:5c:7a:52", ATTR{type}=="1", KERNEL=="eth*", NAME="eth5"（这是旧网卡的信息） # PCI device 0x8086:0x10fb (ixgbe) SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="90:e2:ba:00:1d:b0", ATTR{type}=="1", KERNEL=="eth*", NAME="eth4" （这是新网卡的信息， 把网卡名称换成旧网卡的名称） # PCI device 0x8086:0x10fb (ixgbe) SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="90:e2:ba:00:1d:b1", ATTR{type}=="1", KERNEL=="eth*", NAME="eth5" （这是新网卡的信息， 把网卡名称换成旧网卡的名称） 注意，网卡换过一次就会在这个文件中添加一条记录，这里我们把更换掉的网卡给注释掉了
3.修改网卡的配置文件，把网卡的mac地址给注释掉了
[root@bj ~]# cat /etc/sysconfig/network-scripts/ifcfg-eth4
DEVICE=eth4 #HWADDR=00:0a:f7:5c:7a:50 把网卡的mac地址给注释掉了 TYPE=Ethernet ONBOOT=yes NM_CONTROLLED=no BOOTPROTO=none BRIDGE=cloudbr0 #IPADDR= #NETMASK= #GATEWAY= #DNS1= #DNS2=
4.重启服务器（查看网卡是亮灯就成功连接到交换机）可以通信