网卡工作正常的ifconfig eth0
eth0 Link encap:Ethernet HWaddr 00:0C:299:BA:37

inet addr:10.4.20.35 Bcast:10.4.20.255 Mask:255.255.255.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:1089 errors:0 dropped:0 overruns:0 frame:0
TX packets:157 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:100
RX bytes:117076 (114.3 Kb) TX bytes:17487 (17.0 Kb)
Interrupt:10 Base address:0x10e0
网卡不工作的ifconfig eth0
eth0 Link encap:Ethernet HWaddr 00:0C:299:BA:37

BROADCAST MULTICAST MTU:1500 Metric:1
RX packets:1207 errors:0 dropped:0 overruns:0 frame:0
TX packets:182 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:100
RX bytes:128643 (125.6 Kb) TX bytes:20501 (20.0 Kb)
Interrupt:10 Base address:0x10e0