查看Linux下网卡连接/工作状态（up还是down)?

第1种方法

[root@localhost /]# ifconfig -a
eth0 Link encap:Ethernet HWaddr 00:09:6B:09:08:FC
inet addr:192.168.10.1 Bcast:192.168.10.255 Mask:255.255.255.0
inet6 addr: fe80::209:6bff:fe09:8fc/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:106732953 errors:0 dropped:0 overruns:0 frame:0
TX packets:104379788 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:100
RX bytes:2351331877 (2.1 GiB) TX bytes:391707945 (373.5 MiB)
Base address:0x2500 Memory:fbfe0000-fc000000
eth1 Link encap:Ethernet HWaddr 00:09:6B:09:08:FD
BROADCAST MULTICAST MTU:1500 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:0 (0.0 b) TX bytes:0 (0.0 b)
Base address:0x2540 Memory:fbfc0000-fbfe0000

[root@localhost /root]# ifconfig
eth0 Link encap:Ethernet HWaddr 00:19:DB:41:08:1B
inet addr:211.100.10.235 Bcast:211.100.10.235 Mask:255.255.255.255
UP BROADCAST RUNNING PROMISC MULTICAST MTU:1500 Metric:1
RX packets:178812 errors:0 dropped:0 overruns:0 frame:0
TX packets:153415 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:100
RX bytes:33094019 (31.5 MiB) TX bytes:71911163 (68.5 MiB)
Base address:0x8f00 Memory:fd6e0000-fd700000

eth1 Link encap:Ethernet HWaddr 00:19:DB:41:08:1C
inet addr:192.168.1.115 Bcast:192.168.1.255 Mask:255.255.255.0
UP BROADCAST MULTICAST MTU:1500 Metric:1
RX packets:13805 errors:0 dropped:0 overruns:0 frame:0
TX packets:11356 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:1520439 (1.4 MiB) TX bytes:5406527 (5.1 MiB)
Base address:0x7f00 Memory:fd2e0000-fd300000

eth2 Link encap:Ethernet HWaddr 00:19:DB:41:08:1D
inet addr:202.194.99.62 Bcast:202.194.99.62 Mask:255.255.255.255
UP BROADCAST RUNNING PROMISC MULTICAST MTU:1500 Metric:1
RX packets:158024 errors:0 dropped:0 overruns:0 frame:0
TX packets:182280 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:74748049 (71.2 MiB) TX bytes:33535454 (31.9 MiB)
Base address:0xdf00 Memory:fdee0000-fdf00000

lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:99 errors:0 dropped:0 overruns:0 frame:0
TX packets:99 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:12978 (12.6 kiB) TX bytes:12978 (12.6 kiB)

第二种方法，通过mii-tool指令

[root@localhost root]# mii-tool
eth0: negotiated 100baseTx-FD, link ok
eth1: no link
或
[root@localhost root]# mii-tool -v
eth0: negotiated 100baseTx-FD, link ok
product info: vendor 00:50:43, model 2 rev 3
basic mode: autonegotiation enabled
basic status: autonegotiation complete, link ok
capabilities: 100baseTx-FD 100baseTx-HD 10baseT-FD 10baseT-HD
advertising: 100baseTx-FD 100baseTx-HD 10baseT-FD 10baseT-HD flow-control
link partner: 100baseTx-FD 100baseTx-HD 10baseT-FD 10baseT-HD
eth1: no link
product info: vendor 00:50:43, model 2 rev 3
basic mode: autonegotiation enabled
basic status: no link
capabilities: 100baseTx-FD 100baseTx-HD 10baseT-FD 10baseT-HD
advertising: 100baseTx-FD 100baseTx-HD 10baseT-FD 10baseT-HD flow-control
或

[root@localhost root]# mii-tool -w
21:20:33 eth0: negotiated 100baseTx-FD, link ok
21:20:33 eth1: no link

第三种方法

ethtool eth0

Settings for eth0:
Link detected: yes

http://hi.baidu.com/nan5715077/blog/item/4bd02f071b5f01ca7a8947cd.html

FAQ：如何查看Linux下网卡是否连接(UP)？

FAQ：如何查看Linux下网卡是否连接(UP)？ 来自： 杨志刚 博客 (http://yangzhigang.cublog.cn) //如何不到服务器端，通过指令判断Linux的网卡是否已经连接到网络并为UP状态。有的人用ifconfig -a 查网卡已经配置的正确的IP地址，可是就是ping不能网络，到机房一看网线没接，^@^! 网络不通 会有好多原因，但最先查的就是网卡的网络是还已连接并UP。就像办公室的MM喊着说上不了网 ，结果“本地连接”都是“X”的一样的情况。 本FAQ将帮助您如何不到服务器端，通过指令判断Linux的网卡是否已经连接到网络并为UP状态！ ASK： 1) 通过mii-tool指令 [root@localhost root]# mii-tool eth0: negotiated 100baseTx-FD, link ok eth1: no link 或 [root@localhost root]# mii-tool -v eth0: negotiated 100baseTx-FD, link ok product info: vendor 00:50:43, model 2 rev 3 basic mode: autonegotiation enabled basic status: autonegotiation complete, link ok capabilities: 100baseTx-FD 100baseTx-HD 10baseT-FD 10baseT-HD advertising: 100baseTx-FD 100baseTx-HD 10baseT-FD 10baseT-HD flow-control link partner: 100baseTx-FD 100baseTx-HD 10baseT-FD 10baseT-HD eth1: no link product info: vendor 00:50:43, model 2 rev 3 basic mode: autonegotiation enabled basic status: no link capabilities: 100baseTx-FD 100baseTx-HD 10baseT-FD 10baseT-HD advertising: 100baseTx-FD 100baseTx-HD 10baseT-FD 10baseT-HD flow-control 或 [root@localhost root]# mii-tool -w 21:20:33 eth0: negotiated 100baseTx-FD, link ok 21:20:33 eth1: no link //mii-tool主要是用于配置网卡工作模式的指令，同时也可以进行查询、监控等工作！ 2) [root@localhost /]# /etc/init.d/network status Configured devices: lo eth0 eth1 Currently active devices: lo eth0 等同于 [root@localhost root]# service --status-all ............ ............ Configured devices: lo eth0 eth1 Currently active devices: lo eth0 ............ ............ 3)ifconfig -a [root@localhost /]# ifconfig -a eth0 Link encap:Ethernet HWaddr 00:09:6B:09:08:FC inet addr:192.168.10.1 Bcast:192.168.10.255 Mask:255.255.255.0 inet6 addr: fe80::209:6bff:fe09:8fc/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:106732953 errors:0 dropped:0 overruns:0 frame:0 TX packets:104379788 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:100 RX bytes:2351331877 (2.1 GiB) TX bytes:391707945 (373.5 MiB) Base address:0x2500 Memory:fbfe0000-fc000000 eth1 Link encap:Ethernet HWaddr 00:09:6B:09:08:FD BROADCAST MULTICAST MTU:1500 Metric:1 RX packets:0 errors:0 dropped:0 overruns:0 frame:0 TX packets:0 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:0 (0.0 b) TX bytes:0 (0.0 b) Base address:0x2540 Memory:fbfc0000-fbfe0000 http://blog.chinaunix.net/u2/71257/showart_973425.html