查看网络配置

 步骤

实现此案例需要按照如下步骤进行。
步骤一：根据以下要求查看接口信息

分别查看物理网卡、lo回环接口的信息。
命令操作如下所示：

[root@localhost 桌面]# ifconfig eth0      //查看eth0网卡信息
eth0      Link encap:Ethernet  HWaddr 00:0C:29:0D:06:9A  
          inet addr:192.168.1.1  Bcast:192.168.1.255  Mask:255.255.255.0
          inet6 addr: fe80::20c:29ff:fe0d:69a/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:10596 errors:0 dropped:0 overruns:0 frame:0
          TX packets:74 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:757148 (739.4 KiB)  TX bytes:10154 (9.9 KiB)

[root@localhost 桌面]# ifconfig lo        //查看lo回环接口信息
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:80 errors:0 dropped:0 overruns:0 frame:0
          TX packets:80 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:6328 (6.1 KiB)  TX bytes:6328 (6.1 KiB)
 [root@localhost 桌面]#

列出所有的网络接口，命令操作如下所示：

[root@localhost 桌面]# ifconfig -a
eth0      Link encap:Ethernet  HWaddr 00:0C:29:0D:06:9A  
          inet addr:192.168.1.1  Bcast:192.168.1.255  Mask:255.255.255.0
          inet6 addr: fe80::20c:29ff:fe0d:69a/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:16800 errors:0 dropped:0 overruns:0 frame:0
          TX packets:74 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:1201546 (1.1 MiB)  TX bytes:10154 (9.9 KiB)

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:80 errors:0 dropped:0 overruns:0 frame:0
          TX packets:80 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:6328 (6.1 KiB)  TX bytes:6328 (6.1 KiB)

[root@localhost 桌面]#

步骤二：ping一下网关地址，然后查看ARP缓存表

分析： 利用dhclient命令来获取网关与IP地址。
命令操作如下所示：

[root@localhost 桌面]# dhclient –r       //释放现有IP地址
[root@localhost 桌面]# dhclient           //从新获取
[root@localhost 桌面]# ifconfig eth0
eth0      Link encap:Ethernet  HWaddr 00:0C:29:0D:06:9A  
          inet addr:192.168.30.124  Bcast:192.168.30.255  Mask:255.255.255.0
          inet6 addr: fe80::20c:29ff:fe0d:69a/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:25598 errors:0 dropped:0 overruns:0 frame:0
          TX packets:98 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:1811539 (1.7 MiB)  TX bytes:13766 (13.4 KiB)

[root@localhost 桌面]# route –n     //查看路由表
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
192.168.30.0    0.0.0.0         255.255.255.0   U     0      0        0 eth0
0.0.0.0         192.168.30.2    0.0.0.0         UG    0      0        0 eth0
[root@localhost 桌面]# ping 192.168.30.2   //与网关通信
PING 192.168.30.2 (192.168.30.2) 56(84) bytes of data.
64 bytes from 192.168.30.2: icmp_seq=1 ttl=64 time=50.4 ms
64 bytes from 192.168.30.2: icmp_seq=2 ttl=64 time=83.3 ms
64 bytes from 192.168.30.2: icmp_seq=3 ttl=64 time=5.55 ms
^C        //按ctrl+c结束
--- 192.168.30.2 ping statistics ---
3 packets transmitted, 3 received, 0% packet loss, time 2374ms
rtt min/avg/max/mdev = 5.557/46.480/83.388/31.900 ms
[root@localhost 桌面]# arp –an        //查看ARP缓存表
? (192.168.30.2) at 50:bd:5f:35:f7:b2 [ether] on eth0
[root@localhost 桌面]#

步骤三：查看本机的路由表

命令操作如下所示：

[root@localhost 桌面]# route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
192.168.30.0    0.0.0.0         255.255.255.0   U     0      0        0 eth0
0.0.0.0         192.168.30.2    0.0.0.0         UG    0      0        0 eth0
[root@localhost 桌面]#

步骤四：开启临时服务rsync

查询rsync服务的端口号（/etc/services ）。
命令操作如下所示：

[root@localhost 桌面]# rpm -q rsync      //查询本机是否安装rsync
rsync-3.0.6-9.el6_4.1.x86_64
[root@localhost 桌面]# rpm -q xinetd     //查询本机是否安装xinetd
xinetd-2.3.14-39.el6_4.x86_64
[root@localhost 桌面]# ls /etc/xinetd.d/rsync 
/etc/xinetd.d/rsync
[root@localhost 桌面]#
[root@localhost 桌面]# grep disable /etc/xinetd.d/rsync
	disable	= yes
[root@localhost 桌面]# chkconfig rsync on    //将yes改成no
[root@localhost 桌面]# grep disable /etc/xinetd.d/rsync
	disable	= no
[root@localhost 桌面]# /etc/init.d/xinetd restart
停止 xinetd：                                              [失败]
正在启动 xinetd：                                          [确定]
[root@localhost 桌面]# grep rsync /etc/services 
rsync           873/tcp                         # rsync
rsync           873/udp                         # rsync
.. ..
利用netstat命令查看系统是否在监听此端口。
命令操作如下所示：
[root@localhost 桌面]# netstat -anptu | grep 873
tcp        0      0 :::873                      :::*         LISTEN      3186/xinetd         
[root@localhost 桌面]#