linux网络管理之网络参数设置
（1）ifconfig：查询、设置网卡与IP网络等相关参数。
（2）ifup、ifdown：启动，关闭网卡
（3）route：查看配置路由表
（4）ip：整合式命令，可以直接修改上述描述的参数
1.ifconfig
功能：手动启动、查看与修改网络接口的相关参数。
语法：ifconfig {interface} {options}
interface：网卡接口名称。
options：可以使用的参数：
up，down：启动关闭网卡
mtu：设置不同的mtu值（注解：https://www.cnblogs.com/keystone/p/11410659.html）
netmask：子网掩码
broadcast：广播地址
例1：查看所有的网络接口
[root@localhost ~]# ifconfig eth0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500 inet 192.168.42.180 netmask 255.255.255.0 broadcast 192.168.42.255 inet6 fe80::20c:29ff:fe4f:64e7 prefixlen 64 scopeid 0x20<link> ether 00:0c:29:4f:64:e7 txqueuelen 1000 (Ethernet) RX packets 44964 bytes 36769279 (35.0 MiB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 26366 bytes 3381897 (3.2 MiB) 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 232 bytes 27098 (26.4 KiB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 232 bytes 27098 (26.4 KiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
列出eth0网卡的信息
[root@localhost ~]# ifconfig eth0 eth0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500 inet 192.168.42.180 netmask 255.255.255.0 broadcast 192.168.42.255 inet6 fe80::20c:29ff:fe4f:64e7 prefixlen 64 scopeid 0x20<link> ether 00:0c:29:4f:64:e7 txqueuelen 1000 (Ethernet) RX packets 45056 bytes 36776524 (35.0 MiB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 26417 bytes 3387497 (3.2 MiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
例2：修改网口IP
[root@localhost ~]# ifconfig eth0 192.168.42.200 Connection closed by foreign host. Disconnected from remote host(192.168.42.180:22) at 22:25:57. Type `help' to learn how to use Xshell prompt. [c:\~]$ ssh 192.168.42.200 Connecting to 192.168.42.200:22... Connection established. To escape to local shell, press 'Ctrl+Alt+]'. WARNING! The remote SSH server rejected X11 forwarding request. Last login: Wed Nov 20 21:44:49 2019 from 192.168.42.1 [root@localhost ~]# ifconfig eth0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500 inet 192.168.42.200 netmask 255.255.255.0 broadcast 192.168.42.255 inet6 fe80::20c:29ff:fe4f:64e7 prefixlen 64 scopeid 0x20<link> ether 00:0c:29:4f:64:e7 txqueuelen 1000 (Ethernet) RX packets 45320 bytes 36802465 (35.0 MiB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 26544 bytes 3403897 (3.2 MiB) 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 232 bytes 27098 (26.4 KiB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 232 bytes 27098 (26.4 KiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
[root@localhost ~]# ifconfig eth0 192.168.42.200 netmask 255.255.255.0 gateway 192.168.42.2 broadcast 192.168.42.255 mtu 1000 [root@localhost ~]# ifconfig eth0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500 inet 192.168.42.200 netmask 255.255.255.0 broadcast 192.168.42.255 inet6 fe80::20c:29ff:fe4f:64e7 prefixlen 64 scopeid 0x20<link> ether 00:0c:29:4f:64:e7 txqueuelen 1000 (Ethernet) RX packets 45998 bytes 36872352 (35.1 MiB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 26965 bytes 3457938 (3.2 MiB) 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 232 bytes 27098 (26.4 KiB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 232 bytes 27098 (26.4 KiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
[root@localhost ~]# ifconfig eth0 mtu 800 [root@localhost ~]# [root@localhost ~]# ifconfig eth0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 800 inet 192.168.42.180 netmask 255.255.255.0 broadcast 192.168.42.255 ether 00:0c:29:4f:64:e7 txqueuelen 1000 (Ethernet) RX packets 46105 bytes 36881632 (35.1 MiB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 27012 bytes 3464246 (3.3 MiB) 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 232 bytes 27098 (26.4 KiB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 232 bytes 27098 (26.4 KiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
绑定IP
[root@localhost ~]# ifconfig eth0:0 192.168.42.201 [root@localhost ~]# ifconfig eth0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 800 inet 192.168.42.180 netmask 255.255.255.0 broadcast 192.168.42.255 ether 00:0c:29:4f:64:e7 txqueuelen 1000 (Ethernet) RX packets 46210 bytes 36890938 (35.1 MiB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 27071 bytes 3472671 (3.3 MiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 eth0:0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 800 inet 192.168.42.201 netmask 255.255.255.0 broadcast 192.168.42.255 ether 00:0c:29:4f:64:e7 txqueuelen 1000 (Ethernet) 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 232 bytes 27098 (26.4 KiB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 232 bytes 27098 (26.4 KiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 [root@localhost ~]# ip a 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN qlen 1 link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 inet 127.0.0.1/8 scope host lo valid_lft forever preferred_lft forever inet6 ::1/128 scope host valid_lft forever preferred_lft forever 2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 800 qdisc pfifo_fast state UP qlen 1000 link/ether 00:0c:29:4f:64:e7 brd ff:ff:ff:ff:ff:ff inet 192.168.42.180/24 brd 192.168.42.255 scope global dynamic eth0 valid_lft 1713sec preferred_lft 1713sec inet 192.168.42.200/24 brd 192.168.42.255 scope global secondary eth0 valid_lft forever preferred_lft forever inet 192.168.42.201/24 brd 192.168.42.255 scope global secondary eth0:0 valid_lft forever preferred_lft forever
关闭网卡
[root@localhost ~]# ifconfig eth0:0 down [root@localhost ~]# ifconfig eth0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 800 inet 192.168.42.180 netmask 255.255.255.0 broadcast 192.168.42.255 ether 00:0c:29:4f:64:e7 txqueuelen 1000 (Ethernet) RX packets 46345 bytes 36902353 (35.1 MiB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 27146 bytes 3486767 (3.3 MiB) 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 232 bytes 27098 (26.4 KiB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 232 bytes 27098 (26.4 KiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
以上设置都是临时生效，重启网卡后即失效
例3：启动和关闭网卡
[root@localhost ~]# ifup eth0 [root@localhost ~]# [root@localhost ~]# ifdown eth0
该命名实际上是执行的脚本文件，执行命令后，会到/etc/sysconfig/network-script/下找对应网口文件。若网口文件不存在，则也就使用不了此命令。
2.route
例4：查看路由
[root@localhost ~]# route -n Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface 0.0.0.0 192.168.42.2 0.0.0.0 UG 100 0 0 eth0 192.168.42.0 0.0.0.0 255.255.255.0 U 100 0 0 eth0
Destination，Genmask：network与netmask，两个值确定了一个网络。
Gateway：该网络是通过那个网关出去的，如果现实0.0.0.0表示该路由是直接由本机传送，也就是可以通过局域网的MAC直接发送；如果现实IP则表示路由需要经过路由（网关）的帮忙才能发送出去
Flags：U：该路由是启动的。
H：目标是一台主机而非网络
G:需要通过外部的主机来传递数据包。
R：使用动态路由时，恢复路由标志
D：动态路由
Iface：路由传递数据包的接口
例5：路由的增加与删除
在192.168.42.180节点上绑定一个10.0.0.120的地址
[root@localhost ~]# ifconfig eth0:0 10.0.0.120 [root@localhost ~]# [root@localhost ~]# ip a 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN qlen 1 link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 inet 127.0.0.1/8 scope host lo valid_lft forever preferred_lft forever inet6 ::1/128 scope host valid_lft forever preferred_lft forever 2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 800 qdisc pfifo_fast state UP qlen 1000 link/ether 00:0c:29:4f:64:e7 brd ff:ff:ff:ff:ff:ff inet 192.168.42.180/24 brd 192.168.42.255 scope global dynamic eth0 valid_lft 1716sec preferred_lft 1716sec inet 10.0.0.120/8 brd 10.255.255.255 scope global eth0:0 valid_lft forever preferred_lft forever
在192.168.42.181上添加路由后访问
[root@localhost ~]# route add -net 10.0.0.0/24 dev eth0 [root@localhost ~]# route -n Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface 0.0.0.0 192.168.42.2 0.0.0.0 UG 100 0 0 eth0 10.0.0.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0 192.168.42.0 0.0.0.0 255.255.255.0 U 100 0 0 eth0 [root@localhost ~]# ping 10.0.0.120 PING 10.0.0.120 (10.0.0.120) 56(84) bytes of data. 64 bytes from 10.0.0.120: icmp_seq=1 ttl=64 time=0.832 ms 64 bytes from 10.0.0.120: icmp_seq=2 ttl=64 time=0.369 ms ^C --- 10.0.0.120 ping statistics --- 2 packets transmitted, 2 received, 0% packet loss, time 1008ms rtt min/avg/max/mdev = 0.369/0.600/0.832/0.232 ms
[root@localhost ~]# route -n
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
0.0.0.0 192.168.42.2 0.0.0.0 UG 0 0 0 eth0
0.0.0.0 192.168.42.2 0.0.0.0 UG 100 0 0 eth0
10.0.0.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0
192.168.42.0 0.0.0.0 255.255.255.0 U 100 0 0 eth0
删除路由
[root@localhost ~]# route del default gw 192.168.42.2
[root@localhost ~]# route -n
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
0.0.0.0 192.168.42.2 0.0.0.0 UG 100 0 0 eth0
10.0.0.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0
192.168.42.0 0.0.0.0 255.255.255.0 U 100 0 0 eth0
3.ip
语法：ip [option] [动作] [命令]
选项与参数：
option：设置的参数，主要有：
-s：显示出设备的统计数据，例如：接收到数据包的总数等。
操作：
link：与设备相关的设置，包括MTU，MAC地址等
addr/address:多个IP的实现
route：与路由有关的相关设置
3.1 关于接口设备的相关设置
ip link可以设置与设备（device）有关的相关参数，包括MTU以及该网络接口的MAC等，当然也可以启动或关闭某一个网络接口，
例6：显示本机所有的接口信息
[root@localhost ~]# ip link show 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT qlen 1 link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP mode DEFAULT qlen 1000 link/ether 00:0c:29:14:b5:f9 brd ff:ff:ff:ff:ff:ff
[root@localhost ~]# ip link show eth0 2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP mode DEFAULT qlen 1000 link/ether 00:0c:29:14:b5:f9 brd ff:ff:ff:ff:ff:ff
[root@localhost ~]# ip -s link show eth0 2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP mode DEFAULT qlen 1000 link/ether 00:0c:29:14:b5:f9 brd ff:ff:ff:ff:ff:ff RX: bytes packets errors dropped overrun mcast 27137997 24688 0 0 0 0 TX: bytes packets errors dropped carrier collsns 856945 10922 0 0 0 0
例7：网卡的启动与关闭
[root@localhost ~]# ip link set eth0:0 down Connection closed by foreign host. Disconnected from remote host(192.168.42.180:22) at 23:27:50. Type `help' to learn how to use Xshell prompt.
[root@localhost ~]# ip link set eth0 up
例8：ip命令设置mtu
[root@localhost ~]# ifconfig eth0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500 inet 192.168.42.181 netmask 255.255.255.0 broadcast 192.168.42.255 inet6 fe80::20c:29ff:fe14:b5f9 prefixlen 64 scopeid 0x20<link> ether 00:0c:29:14:b5:f9 txqueuelen 1000 (Ethernet) RX packets 24942 bytes 27160114 (25.9 MiB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 11046 bytes 871704 (851.2 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 30 bytes 1622 (1.5 KiB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 30 bytes 1622 (1.5 KiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 [root@localhost ~]# ip link set eth0 mtu 1000 [root@localhost ~]# ifconfig eth0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1000 inet 192.168.42.181 netmask 255.255.255.0 broadcast 192.168.42.255 ether 00:0c:29:14:b5:f9 txqueuelen 1000 (Ethernet) RX packets 25015 bytes 27166560 (25.9 MiB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 11083 bytes 876951 (856.3 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 30 bytes 1622 (1.5 KiB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 30 bytes 1622 (1.5 KiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
例9：修改网卡名与mac
[root@localhost ~]# ip link set eth0 name aaa RTNETLINK answers: Device or resource busy [root@localhost ~]# ip link set eth1 down [root@localhost ~]# ip link set eth1 name aaa [root@localhost ~]# ip link show 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT qlen 1 link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 800 qdisc pfifo_fast state UP mode DEFAULT qlen 1000 link/ether 00:0c:29:4f:64:e7 brd ff:ff:ff:ff:ff:ff 3: aaa: <BROADCAST,MULTICAST> mtu 1500 qdisc pfifo_fast state DOWN mode DEFAULT qlen 1000 link/ether 00:0c:29:4f:64:f1 brd ff:ff:ff:ff:ff:ff
[root@localhost ~]# ip link set aaa address aa:aa:aa:aa:aa:aa [root@localhost ~]# ip link show 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT qlen 1 link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 800 qdisc pfifo_fast state UP mode DEFAULT qlen 1000 link/ether 00:0c:29:4f:64:e7 brd ff:ff:ff:ff:ff:ff 3: aaa: <BROADCAST,MULTICAST> mtu 1500 qdisc pfifo_fast state DOWN mode DEFAULT qlen 1000 link/ether aa:aa:aa:aa:aa:aa brd ff:ff:ff:ff:ff:ff
3.2 关于额外IP的相关设定：
主要是在设置与ip有关的各项参数，包括netmask、broadcast等。
例10：查看ip参数
[root@localhost ~]# ip address show 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN qlen 1 link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 inet 127.0.0.1/8 scope host lo valid_lft forever preferred_lft forever inet6 ::1/128 scope host valid_lft forever preferred_lft forever 2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 800 qdisc pfifo_fast state UP qlen 1000 link/ether 00:0c:29:4f:64:e7 brd ff:ff:ff:ff:ff:ff inet 192.168.42.180/24 brd 192.168.42.255 scope global dynamic eth0 valid_lft 1731sec preferred_lft 1731sec 3: aaa: <BROADCAST,MULTICAST> mtu 1500 qdisc pfifo_fast state DOWN qlen 1000 link/ether aa:aa:aa:aa:aa:aa brd ff:ff:ff:ff:ff:ff [root@localhost ~]# ip a s 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN qlen 1 link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 inet 127.0.0.1/8 scope host lo valid_lft forever preferred_lft forever inet6 ::1/128 scope host valid_lft forever preferred_lft forever 2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 800 qdisc pfifo_fast state UP qlen 1000 link/ether 00:0c:29:4f:64:e7 brd ff:ff:ff:ff:ff:ff inet 192.168.42.180/24 brd 192.168.42.255 scope global dynamic eth0 valid_lft 1726sec preferred_lft 1726sec 3: aaa: <BROADCAST,MULTICAST> mtu 1500 qdisc pfifo_fast state DOWN qlen 1000 link/ether aa:aa:aa:aa:aa:aa brd ff:ff:ff:ff:ff:ff
例11：添加网络接口
[root@localhost ~]# ip addr add 192.168.42.200/24 dev eth0 label eth0:0 [root@localhost ~]# ifconfig eth0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 800 inet 192.168.42.180 netmask 255.255.255.0 broadcast 192.168.42.255 ether 00:0c:29:4f:64:e7 txqueuelen 1000 (Ethernet) RX packets 48674 bytes 37107043 (35.3 MiB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 28250 bytes 3636665 (3.4 MiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 eth0:0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 800 inet 192.168.42.200 netmask 255.255.255.0 broadcast 0.0.0.0 ether 00:0c:29:4f:64:e7 txqueuelen 1000 (Ethernet) 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 234 bytes 27309 (26.6 KiB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 234 bytes 27309 (26.6 KiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
例12：删除添加的接口
[root@localhost ~]# ip addr del 192.168.42.200/24 dev eth0 label eth0:0 [root@localhost ~]# ifconfig eth0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 800 inet 192.168.42.180 netmask 255.255.255.0 broadcast 192.168.42.255 ether 00:0c:29:4f:64:e7 txqueuelen 1000 (Ethernet) RX packets 48807 bytes 37118961 (35.3 MiB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 28326 bytes 3647272 (3.4 MiB) 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 234 bytes 27309 (26.6 KiB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 234 bytes 27309 (26.6 KiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
3.3关于路由的相关设定
例13 ：显示当前的路由信息
[root@localhost ~]# ip route show default via 192.168.42.2 dev eth0 proto static metric 100 192.168.42.0/24 dev eth0 proto kernel scope link src 192.168.42.180 metric 100
例14：添加路由，主要是本机直接可联通的网络
在192.168.42.180上添加10.0.0.10网口
[root@localhost ~]# ip addr add 10.0.0.10/24 dev eth0 label eth0:0 [root@localhost ~]# ifconfig eth0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 800 inet 192.168.42.180 netmask 255.255.255.0 broadcast 192.168.42.255 ether 00:0c:29:4f:64:e7 txqueuelen 1000 (Ethernet) RX packets 49183 bytes 37152239 (35.4 MiB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 28542 bytes 3673127 (3.5 MiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 eth0:0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 800 inet 10.0.0.10 netmask 255.255.255.0 broadcast 0.0.0.0 ether 00:0c:29:4f:64:e7 txqueuelen 1000 (Ethernet) 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 234 bytes 27309 (26.6 KiB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 234 bytes 27309 (26.6 KiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
在192.168.42.181上添加静态路由
[root@localhost ~]# ip route add 10.0.0.0/24 dev eth0 [root@localhost ~]# ip route show default via 192.168.42.2 dev eth0 proto static metric 100 10.0.0.0/24 dev eth0 scope link 192.168.42.0/24 dev eth0 proto kernel scope link src 192.168.42.181 metric 100 [root@localhost ~]# ping 10.0.0.10 PING 10.0.0.10 (10.0.0.10) 56(84) bytes of data. 64 bytes from 10.0.0.10: icmp_seq=1 ttl=64 time=0.458 ms 64 bytes from 10.0.0.10: icmp_seq=2 ttl=64 time=0.269 ms ^C --- 10.0.0.10 ping statistics --- 2 packets transmitted, 2 received, 0% packet loss, time 1000ms rtt min/avg/max/mdev = 0.269/0.363/0.458/0.096 ms
例15 增加可以通往外部的路由
[root@localhost ~]# ip route add 192.168.192.0/24 via 192.168.42.181 dev eth0 [root@localhost ~]# route -n Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface 0.0.0.0 192.168.42.2 0.0.0.0 UG 100 0 0 eth0 192.168.42.0 0.0.0.0 255.255.255.0 U 100 0 0 eth0 192.168.192.0 192.168.42.181 255.255.255.0 UG 0 0 0 eth0
例16：增加静态路由
[root@localhost ~]# ip route add default via 192.168.42.2 dev eth0 [root@localhost ~]# route -n Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface 0.0.0.0 192.168.42.2 0.0.0.0 UG 0 0 0 eth0 0.0.0.0 192.168.42.2 0.0.0.0 UG 100 0 0 eth0 192.168.42.0 0.0.0.0 255.255.255.0 U 100 0 0 eth0 192.168.192.0 192.168.42.181 255.255.255.0 UG 0 0 0 eth0
例17：删除路由
[root@localhost ~]# route -n Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface 0.0.0.0 192.168.42.2 0.0.0.0 UG 0 0 0 eth0 0.0.0.0 192.168.42.2 0.0.0.0 UG 100 0 0 eth0 192.168.42.0 0.0.0.0 255.255.255.0 U 100 0 0 eth0 192.168.192.0 192.168.42.181 255.255.255.0 UG 0 0 0 eth0 [root@localhost ~]# ip route del 192.168.192.0/24 [root@localhost ~]# ip route del default [root@localhost ~]# route -n Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface 0.0.0.0 192.168.42.2 0.0.0.0 UG 100 0 0 eth0 192.168.42.0 0.0.0.0 255.255.255.0 U 100 0 0 eth0
