After install redhat7 os ,wo can use ifconfig command to find out the network connection.However ,sometimes eth0 ethernet port is not in the list.
Solution:
(1)Enter the directory：
#cd /etc/sysconfig/network-scripts/
(2)Create or copy a file：
#vim /etc/sysconfig/network-scripts/ifcfg-eth0
or
#cp ifcfg-l0 ifcfg-eth0
(3)Copy the setting from ifcfg-l0,then modify the setting
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DEVICE=eth0
IPADDR=192.168.1.110
NETMASK=255.255.255.0
NETWORK=192.168.1.0
GATEWAY=192.168.1.1
BROADCAST=192.168.1.255
ONBOOT=[yes]
BOOTPROTO=[none|static|bootp|dhcp]
HWADDR=00:13:D3:27:9F:80
NAME=eth0
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(4)Create a file [70-persistent-net.rules ], modify the setting
Note:the most important is the MAC address setting
# vim /etc/udev/rules.d/70-persistent-net.rules
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# PCI device 0x10ec:0x8168 (r8169) (custom name provided by external tool)
SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="00:13:D3:27:9F:80", ATTR{type}=="1", KERNEL=="eth*", NAME="eth0"
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