【2017/7/9】解决linux系统NAT模式下无法上网

1.查看一下VMware网络模式、NAT的网段

2.查看IP地址配置

[root@mygod1 ~]# cat /etc/sysconfig/network-scripts/ifcfg-eth0
DEVICE=eth0
TYPE=Ethernet
UUID=01b53d0f-0214-44f2-9c7f-1ae4a1ec56bb
ONBOOT=yes
BOOTPROTO=static
IPADDR=192.168.158.46
NETMASK=255.255.255.0
GATWAY=192.168.158.1
DNS1=192.168.158.2
[root@mygod1 ~]#
[root@mygod1 ~]#

3.无法访问外网

[root@mygod1 ~]# ping www.baidu.com
connect: Network is unreachable
[root@mygod1 ~]#
[root@mygod1 ~]#

4.查看路由表

[root@mygod1 ~]# route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
192.168.158.0   0.0.0.0         255.255.255.0   U     1      0        0 eth0
[root@mygod1 ~]#

5.添加缺少的路由条目

[root@mygod1 ~]# route add default gw 192.168.158.2 dev eth0
[root@mygod1 ~]#
[root@mygod1 ~]#
[root@mygod1 ~]# route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
192.168.158.0   0.0.0.0         255.255.255.0   U     1      0        0 eth0
0.0.0.0         192.168.158.2   0.0.0.0         UG    0      0        0 eth0
[root@mygod1 ~]#

6.成功访问外网

[root@mygod1 ~]# ping www.baidu.com
PING www.a.shifen.com (180.97.33.108) 56(84) bytes of data.
64 bytes from 180.97.33.108: icmp_seq=1 ttl=128 time=13.2 ms
64 bytes from 180.97.33.108: icmp_seq=2 ttl=128 time=13.7 ms
64 bytes from 180.97.33.108: icmp_seq=3 ttl=128 time=14.0 ms
64 bytes from 180.97.33.108: icmp_seq=4 ttl=128 time=14.4 ms
64 bytes from 180.97.33.108: icmp_seq=5 ttl=128 time=15.2 ms
^C
--- www.a.shifen.com ping statistics ---
5 packets transmitted, 5 received, 0% packet loss, time 4797ms
rtt min/avg/max/mdev = 13.268/14.152/15.207/0.651 ms
[root@mygod1 ~]#



7.让路由条目永久生效

[root@mygod1 ~]# cat /etc/rc.local
#!/bin/sh
#
# This script will be executed *after* all the other init scripts.
# You can put your own initialization stuff in here if you don't
# want to do the full Sys V style init stuff.

touch /var/lock/subsys/local
route add default gw 192.168.158.2 dev eth0
[root@mygod1 ~]#