几台机器内外网不通，管理卡登录，ifconfig查看数据包有有很多droped：

eth1      Link encap:Ethernet  HWaddr 08:9E:00:00:00:00  
          inet addr:14.0.0.2  Bcast:14.0.0.255  Mask:255.255.255.0
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:122487852 errors:0 dropped:11825871 overruns:0 frame:0
          TX packets:57810069 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:163984556819 (152.7 GiB)  TX bytes:7077145803 (6.5 GiB)
          Interrupt:16 Memory:f7d00000-f7d20000 

[root@localhost ~]# ip add
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 16436 qdisc noqueue state UNKNOWN
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
    inet6 ::1/128 scope host
       valid_lft forever preferred_lft forever
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
    link/ether 08:9e:01:dc:4b:ce brd ff:ff:ff:ff:ff:ff
    inet 58.63.235.42/25 brd 58.63.235.127 scope global eth0
    inet6 fe80::a9e:1ff:fedc:4bce/64 scope link
       valid_lft forever preferred_lft forever
3: eth1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
    link/ether 08:9e:01:dc:4b:cf brd ff:ff:ff:ff:ff:ff
    inet 10.71.3.42/24 brd 10.71.3.255 scope global eth1
    inet6 fe80::a9e:1ff:fedc:4bcf/64 scope link
       valid_lft forever preferred_lft forever
4: eth2: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN qlen 1000
    link/ether 08:9e:01:dc:4b:d0 brd ff:ff:ff:ff:ff:ff
5: eth3: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN qlen 1000
    link/ether 08:9e:01:dc:4b:d1 brd ff:ff:ff:ff:ff:ff
[root@localhost ~]# lspci |grep Eth
02:00.0 Ethernet controller: Intel Corporation Device 1557 (rev 01)
04:00.0 Ethernet controller: Intel Corporation 82574L Gigabit Network Connection
05:00.0 Ethernet controller: Intel Corporation 82574L Gigabit Network Connection
06:00.0 Ethernet controller: Intel Corporation 82574L Gigabit Network Connection
07:00.0 Ethernet controller: Intel Corporation 82574L Gigabit Network Connection
[root@localhost ~]# ethtool -i eth1
driver: e1000e
version: 2.5.4-NAPI
firmware-version: 2.1-3
bus-info: 0000:05:00.0
[root@localhost ~]# ethtool  eth1
Settings for eth1:
        Supported ports: [ TP ]
        Supported link modes:   10baseT/Half 10baseT/Full
                                100baseT/Half 100baseT/Full
                                1000baseT/Full
        Supports auto-negotiation: Yes
        Advertised link modes:  10baseT/Half 10baseT/Full
                                100baseT/Half 100baseT/Full
                                1000baseT/Full
        Advertised pause frame use: No
        Advertised auto-negotiation: Yes
        Speed: 1000Mb/s
        Duplex: Full
        Port: Twisted Pair
        PHYAD: 1
        Transceiver: internal
        Auto-negotiation: on
        MDI-X: on
        Supports Wake-on: pumbg
        Wake-on: g
        Current message level: 0x00000007 (7)
        Link detected: yes

http://bbs.chinaunix.net/thread-1990685-1-1.html

http://blog.csdn.net/naguang/article/details/8583095

http://yhj1065.blog.163.com/blog/static/1980021720076258544744/