排查经过：查看配置文件，
[root@HGJ0205 ~]# cat /etc/sysconfig/network-scripts/ifcfg-eth0没有问题，
查看网卡
[root@HGJ0205 ~]# ifconfig
eth0 Link encap:Ethernet HWaddr 00:26:55:DF:DD:9E
inet addr:10.12.5.103 Bcast:10.12.5.255 Mask:255.255.255.0
inet6 addr: fe80::226:55ff:fedf:dd9e/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:4885599 errors:0 dropped:0 overruns:0 frame:0
TX packets:5632499 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:1460799376 (1.3 GiB) TX bytes:2154273766 (2.0 GiB)
Interrupt:30 Memory:fdce0000-fdd00000
lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:7752962 errors:0 dropped:0 overruns:0 frame:0
TX packets:7752962 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:3827246039 (3.5 GiB) TX bytes:3827246039 (3.5 GiB)
网卡启动，已经配置了ip,没有问题，检查网关
[root@HGJ0205 ~]# ping 10.12.5.1
发现自己的网关也ping不同。
检查网线状况，发现网线不在集成网卡eth0上，而是在独立配置的网卡上，从而导致配置好网卡信息不是插网线的网卡，也就是说插网线的网卡没有网卡信息，所以不通。
[root@HGJ0205 ~]#cat /etc/udev/rules.d/70-persistent-net.rules
# This file was automatically generated bythe /lib/udev/write_net_rules
# program, run by thepersistent-net-generator.rules rules file.
#
# You can modify it, as long as you keepeach rule on a single
# line, and change only the value of theNAME= key.
# PCI device 0x8086:0x105e (e1000e) (customname provided by external tool)
SUBSYSTEM=="net",ACTION=="add", DRIVERS=="?*", ATTR{address}=="00:26:55:df:dd:9f",ATTR{type}=="1", KERNEL=="eth*", NAME="eth3"
# PCI device 0x8086:0x105e (e1000e) (customname provided by external tool)
SUBSYSTEM=="net",ACTION=="add", DRIVERS=="?*", ATTR{address}=="00:26:55:e0:35:ef",ATTR{type}=="1", KERNEL=="eth*", NAME="eth5"
# PCI device 0x14e4:0x164a (bnx2)
SUBSYSTEM=="net",ACTION=="add", DRIVERS=="?*", ATTR{address}=="78:e7:d1:fb:6e:38", ATTR{type}=="1",KERNEL=="eth*", NAME="eth1"
# PCI device 0x8086:0x105e (e1000e) (customname provided by external tool)
SUBSYSTEM=="net",ACTION=="add", DRIVERS=="?*", ATTR{address}=="00:26:55:df:dd:9e",ATTR{type}=="1", KERNEL=="eth*", NAME="eth2"
# PCI device 0x14e4:0x164a (bnx2) (customname provided by external tool)
SUBSYSTEM=="net",ACTION=="add", DRIVERS=="?*", ATTR{address}=="78:e7:d1:fb:6e:3a", ATTR{type}=="1",KERNEL=="eth*", NAME="eth1"
# PCI device 0x8086:0x105e (e1000e) (customname provided by external tool)
SUBSYSTEM=="net",ACTION=="add", DRIVERS=="?*", ATTR{address}=="00:26:55:e0:35:ee",ATTR{type}=="1", KERNEL=="eth*", NAME="eth4"
6个网卡，看着都头晕。
解决方案：既然找到问题解决它。只要把网线接口对应的配置文件配置好久可以，两个解决方案
一、配置好一个网络配置文件，然后把网线一个网口一个网口的测试，通了就说明是这个网卡的。
二、网线不动，一个一个配置所有的网卡，哪个通了也说明是对了
注意：1、千万不要把所有的网卡都配置了测试，ip会冲突。
2、集成网卡和独立网卡的mac地址格式是不一样的，这样可以很快的分辨出你配置的是哪个网卡，红色的是集成网卡的，减少排查步骤。