2017-10-17 1周2次课

一周第二次课（10月17日）
1.6/1.7 配置IP

1.8 网络问题排查

配置IP

 

不管你是使用网桥模式，还是NAT模式，vmware10的虚拟机都是支持自动获取IP的。默认CentOS安装完成后，网卡配置文件是通过dhcp的方式获取ip的，所以我们只需要运行一个命令即可获取到ip，命令是 dhclient

如果你在接下来的试验中发现自动获取到的ip消失了，那么就需要我们手动来配置一个静态IP了。在配置静态IP之前，需要我们做如下操作（适用于NAT模式）：
（1）点一下虚拟机菜单栏的“编辑”选中“虚拟网络编辑器”，选中“vmnet8"那一行（2）点右侧的”NAT设置”，记住网关的ip是什么，比如我的网关地址是“192.168.79.2”

（2）到我们的虚拟机上，也就是CentOS里面，输入命令：
vi /etc/sysconfig/network-scripts/ifcfg-ens33

[root@localhost ~]# cat /etc/sysconfig/network-scripts/ifcfg-ens33 
TYPE=Ethernet
BOOTPROTO=static
DEFROUTE=yes
PEERDNS=yes
PEERROUTES=yes
IPV4_FAILURE_FATAL=no
IPV6INIT=yes
IPV6_AUTOCONF=yes
IPV6_DEFROUTE=yes
IPV6_PEERDNS=yes
IPV6_PEERROUTES=yes
IPV6_FAILURE_FATAL=no
IPV6_ADDR_GEN_MODE=stable-privacy
NAME=ens33
UUID=108cce0a-b5ea-482f-9d48-f744fa3d4347
DEVICE=ens33
ONBOOT=yes
IPADDR=192.168.79.128
NETMASK=255.255.255.0
GATEWAY=192.168.79.2
DNS1=8.8.8.8

[root@localhost ~]#sed -i 's/ONBOOT=no/ONBOOT=yes/' /etc/sysconfig/network-scripts/ifcfg-ens33

[root@localhost ~]#sed -i 's/BOOTPROTO=dhcp/BOOTPROTO=static/'/etc/sysconfig/network-scripts/ifcfg-ens33

[root@localhost ~]#echo "IPADDR=192.168.79.128" >>/etc/sysconfig/network-scripts/ifcfg-ens33

[root@localhost ~]#echo "NETMASK=255.255.255.0" >>/etc/sysconfig/network-scripts/ifcfg-ens33

[root@localhost ~]#echo "GATEWAY=192.168.79.2" >>/etc/sysconfig/network-scripts/ifcfg-ens33

[root@localhost ~]#echo "DNS1=8.8.8.8" >>/etc/sysconfig/network-scripts/ifcfg-ens33

[root@localhost ~]#systemctl restart network.service

（3）使用命令 ifconfig 查看当前网卡的ip，我们还可以加一个 -a选项来查看全部的网卡配置

[root@localhost ~]# ifconfig -a
ens33: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet 192.168.79.128  netmask 255.255.255.0  broadcast 192.168.79.255
        inet6 fe80::6e31:1314:97ad:941d  prefixlen 64  scopeid 0x20<link>
        ether 00:0c:29:9a:64:8f  txqueuelen 1000  (Ethernet)
        RX packets 1949  bytes 155637 (151.9 KiB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 634  bytes 86354 (84.3 KiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0


lo: flags=73<UP,LOOPBACK,RUNNING>  mtu 65536
        inet 127.0.0.1  netmask 255.0.0.0
        inet6 ::1  prefixlen 128  scopeid 0x10<host>
        loop  txqueuelen 1  (Local Loopback)
        RX packets 80  bytes 6936 (6.7 KiB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 80  bytes 6936 (6.7 KiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

[root@localhost ~]# route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
0.0.0.0         192.168.79.2    0.0.0.0         UG    100    0        0 ens33
192.168.79.0    0.0.0.0         255.255.255.0   U     100    0        0 ens33

[root@localhost ~]# ping 192.168.79.2
PING 192.168.79.2 (192.168.79.2) 56(84) bytes of data.
64 bytes from 192.168.79.2: icmp_seq=1 ttl=128 time=0.169 ms
64 bytes from 192.168.79.2: icmp_seq=2 ttl=128 time=0.139 ms
64 bytes from 192.168.79.2: icmp_seq=3 ttl=128 time=0.172 ms
^C
--- 192.168.79.2 ping statistics ---
3 packets transmitted, 3 received, 0% packet loss, time 2001ms
rtt min/avg/max/mdev = 0.139/0.160/0.172/0.014 ms
[root@localhost ~]# 

[root@localhost ~]# ping www.baidu.com
PING www.a.shifen.com (115.239.210.27) 56(84) bytes of data.
64 bytes from 115.239.210.27 (115.239.210.27): icmp_seq=1 ttl=128 time=10.1 ms
64 bytes from 115.239.210.27 (115.239.210.27): icmp_seq=2 ttl=128 time=10.6 ms
^C
--- www.a.shifen.com ping statistics ---
2 packets transmitted, 2 received, 0% packet loss, time 1001ms
rtt min/avg/max/mdev = 10.155/10.386/10.618/0.252 ms

如果没有ifconfig命令就安装

[root@localhost ~]# yum install -y net-tools