ifcfg命令家族:ifconfig,route,netstat
1、NAME
ifconfig – configure a network interface
SYNOPSIS
ifconfig [interface]
# ifconfig -a:显示所有接口,包括inactive状态的接口;
ifconfig interface [aftype] options | address …
# ifconfig IFACE IP/MASK [up|down]
]# ifconfig eth1 192.168.1.100/24
# ifconfig IFACE IP netmask NETMASK
]# ifconfig eth1 192.168.1.100 netmask 255.255.255.0
修改和添加IP
[root@node1 ~]# ifconfig eth1 0 #删除当前IP [root@node1 ~]# ifconfig eth1 eth1 Link encap:Ethernet HWaddr 00:0C:29:AE:E4:E2 inet6 addr: fe80::20c:29ff:feae:e4e2/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:145 errors:0 dropped:0 overruns:0 frame:0 TX packets:18 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:16604 (16.2 KiB) TX bytes:1404 (1.3 KiB) [root@node1 ~]# ifconfig eth1 192.168.1.100/24 up [root@node1 ~]# ifconfig eth1 eth1 Link encap:Ethernet HWaddr 00:0C:29:AE:E4:E2 inet addr:192.168.1.100 Bcast:192.168.1.255 Mask:255.255.255.0 inet6 addr: fe80::20c:29ff:feae:e4e2/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:145 errors:0 dropped:0 overruns:0 frame:0 TX packets:18 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:16604 (16.2 KiB) TX bytes:1404 (1.3 KiB)
]# ifconfig eth1:0 192.168.1.101/24 #ifconfig添加IP必须加label,格式 IFACE:#
]# ifconfig eth1:0 eth1:0 Link encap:Ethernet HWaddr 00:0C:29:AE:E4:E2 inet addr:192.168.1.101 Bcast:192.168.1.255 Mask:255.255.255.0 UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
开启和关闭eth1网卡
]# ifconfig eth1 up
]# ifconfig eth1 down
2、route命令:路由查看及管理
route – show / manipulate the IP routing table
路由条目类型:
主机路由:目标地址为单个IP;
网络路由:目标地址为IP网络;
默认路由:目标为任意网络,0.0.0.0/0.0.0.0
查看:# route -n
[root@node1 ~]# route -n
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
10.0.1.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0
192.168.1.0 0.0.0.0 255.255.255.0 U 0 0 0 eth1
169.254.0.0 0.0.0.0 255.255.0.0 U 1002 0 0 eth0
0.0.0.0 10.0.1.2 0.0.0.0 UG 0 0 0 eth0
添加:route add [-net|-host] target [netmask Nm] [gw GW] [[dev] If]
]# route add -net 10.0.0.0/8 gw 192.168.1.1 dev eth1
]# route add default gw 192.168.1.1
]# route -n
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
10.0.1.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0
192.168.1.0 0.0.0.0 255.255.255.0 U 0 0 0 eth1
169.254.0.0 0.0.0.0 255.255.0.0 U 1002 0 0 eth0
10.0.0.0 192.168.1.1 255.0.0.0 UG 0 0 0 eth1
0.0.0.0 192.168.1.1 0.0.0.0 UG 0 0 0 eth1
0.0.0.0 10.0.1.2 0.0.0.0 UG 0 0 0 eth0
删除:route del [-net|-host] target [gw Gw] [netmask Nm] [[dev] If]
]# route del -net 10.0.0.0/8
]# route del default dev eth1
]# route -n
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
10.0.1.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0
192.168.1.0 0.0.0.0 255.255.255.0 U 0 0 0 eth1
169.254.0.0 0.0.0.0 255.255.0.0 U 1002 0 0 eth0
0.0.0.0 10.0.1.2 0.0.0.0 UG 0 0 0 eth0
3、netstat命令:
Print network connections, routing tables, interface statistics, masquerade connections, and multicast memberships
显示路由表:netstat -rn
-r:显示内核路由表
-n:数字格式
]# netstat -rn
Kernel IP routing table
Destination Gateway Genmask Flags MSS Window irtt Iface
10.0.1.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0
192.168.1.0 0.0.0.0 255.255.255.0 U 0 0 0 eth1
169.254.0.0 0.0.0.0 255.255.0.0 U 0 0 0 eth0
0.0.0.0 10.0.1.2 0.0.0.0 UG 0 0 0 eth0
显示网络连接:
netstat [–tcp|-t] [–udp|-u] [–udplite|-U] [–sctp|-S] [–raw|-w] [–listening|-l] [–all|-a] [–numeric|-n] [–extend|-e[–extend|-e]] [–program|-p]
-t:TCP协议的相关连接,连接均有其状态;FSM(Finate State Machine);
-u:UDP相关的连接
-w:raw socket相关的连接
-l:处于监听状态的连接
-a:所有状态
-n:以数字格式显示IP和Port;
-e:扩展格式
-p:显示相关的进程及PID;
常用组合:
-tan, -uan, -tnl, -unl, -tunlp
]# netstat -tan
Active Internet connections (servers and established)
Proto Recv-Q Send-Q Local Address Foreign Address State
tcp 0 0 0.0.0.0:22 0.0.0.0:* LISTEN
tcp 0 64 10.0.1.6:22 10.0.1.101:52600 ESTABLISHED
tcp 0 0 :::22 :::* LISTEN
]# netstat -tnl
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address Foreign Address State
tcp 0 0 0.0.0.0:22 0.0.0.0:* LISTEN
tcp 0 0 :::22 :::* LISTEN
]# netstat -tunlp
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address Foreign Address State PID/Program name
tcp 0 0 0.0.0.0:22 0.0.0.0:* LISTEN 928/sshd
tcp 0 0 :::22 :::* LISTEN 928/sshd
传输层协议:
tcp:面向连接的协议;通信开始之前,要建立一个虚链路;通信完成后还要拆除连接;
udp:无连接的协议;直接发送数据报文;
显示接口的统计数据:
netstat {–interfaces|-I|-i} [iface] [–all|-a] [–extend|-e] [–verbose|-v] [–program|-p] [–numeric|-n]
所有接口:
netstat -i
指定接口:
netstat -I<IFace>
]# netstat -i
Kernel Interface table
Iface MTU Met RX-OK RX-ERR RX-DRP RX-OVR TX-OK TX-ERR TX-DRP TX-OVR Flg
eth0 1500 0 4791 0 0 0 3900 0 0 0 BMRU
eth1 1500 0 1442 0 0 0 58 0 0 0 BMRU
lo 65536 0 12 0 0 0 12 0 0 0 LRU
]# netstat -Ieth1
Kernel Interface table
Iface MTU Met RX-OK RX-ERR RX-DRP RX-OVR TX-OK TX-ERR TX-DRP TX-OVR Flg
eth1 1500 0 1446 0 0 0 58 0 0 0 BMRU
ifup/ifdown命令:
注意:通过配置文件/etc/sysconfig/network-scripts/ifcfg-IFACE来识别接口并完成配置;
原创文章,作者:N24_ViCi,如若转载,请注明出处:http://www.178linux.com/61050
评论列表(1条)
对于网卡相关的知识,不仅要知道配置方式,也要知道如何查看当前网卡的流量,什么时候流量是高,什么时候网卡传输数据有异常,比如iftop工具等使用。