总结Linux中用于网络信息查看的命令如下。

1 ifconfig

Linux ifconfig命令用于显示或设置网络设备。

常用：

ifconfig

结果：

[root@localhost ~]# ifconfig
eth0      Link encap:Ethernet  HWaddr 00:50:56:BF:26:20  
          inet addr:192.168.120.204  Bcast:192.168.120.255  Mask:255.255.255.0
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:8700857 errors:0 dropped:0 overruns:0 frame:0
          TX packets:31533 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:596390239 (568.7 MiB)  TX bytes:2886956 (2.7 MiB)

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:68 errors:0 dropped:0 overruns:0 frame:0
          TX packets:68 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:2856 (2.7 KiB)  TX bytes:2856 (2.7 KiB)

说明：

eth0 表示第一块网卡， 其中 HWaddr 表示网卡的物理地址，可以看到目前这个网卡的物理地址(MAC地址）是 00:50:56:BF:26:20

inet addr 用来表示网卡的IP地址，此网卡的 IP地址是 192.168.120.204，广播地址， Bcast:192.168.120.255，掩码地址Mask:255.255.255.0 

lo 是表示主机的回坏地址，这个一般是用来测试一个网络程序，但又不想让局域网或外网的用户能够查看，只能在此台主机上运行和查看所用的网络接口。比如把 HTTPD服务器的指定到回坏地址，在浏览器输入 127.0.0.1 就能看到你所架WEB网站了。但只是您能看得到，局域网的其它主机或用户无从知道。

第一行：连接类型：Ethernet（以太网）HWaddr（硬件mac地址）

第二行：网卡的IP地址、子网、掩码

第三行：UP（代表网卡开启状态）RUNNING（代表网卡的网线被接上）MULTICAST（支持组播）MTU:1500（最大传输单元）：1500字节

第四、五行：接收、发送数据包情况统计

第七行：接收、发送数据字节数统计信息。

参考连接： ifconfig

ifconfig -s

Iface      MTU    RX-OK RX-ERR RX-DRP RX-OVR    TX-OK TX-ERR TX-DRP TX-OVR Flg
bond0            1500 30648096      0    404 0      27176356      0      0      0 BMmRU
bond1            9000        0      0      0 0      11983814      0      0      0 BMmRU
bond2            9000        0      0      0 0      11983810      0      0      0 BMmRU
bond0.154        1500  3545291      0    476 0       2984981      0      0      0 BMRU
bond0.199        1500  3456116      0    590 0             8      0      0      0 BMRU
docker0          1500        0      0      0 0             0      0      0      0 BMU
enp61s0f0        1500 13760283      0      0 0      20828526      0      0      0 BMsRU
enp61s0f1        1500 16887978      0      0 0       6347836      0      0      0 BMsRU
ens3f0           9000        0      0      0 0       5991906      0      0      0 BMsRU
ens3f1           9000        0      0      0 0       5991914      0      0      0 BMsRU
ens6f0           9000        0      0      0 0       5991908      0      0      0 BMsRU
ens6f1           9000        0      0      0 0       5991896      0      0      0 BMsRU
lo              65536   798616      0      0 0        798616      0      0      0 LRU

 ifconfig -s 显示摘要信息，类似于 netstat -i

netstat -i

Kernel Interface table
Iface             MTU    RX-OK RX-ERR RX-DRP RX-OVR    TX-OK TX-ERR TX-DRP TX-OVR Flg
bond0            1500 30649171      0    404 0      27177301      0      0      0 BMmRU
bond1            9000        0      0      0 0      11984208      0      0      0 BMmRU
bond2            9000        0      0      0 0      11984204      0      0      0 BMmRU
bond0.154        1500  3545480      0    476 0       2985132      0      0      0 BMRU
bond0.199        1500  3456248      0    590 0             8      0      0      0 BMRU
docker0          1500        0      0      0 0             0      0      0      0 BMU
enp61s0f0        1500 13760823      0      0 0      20829228      0      0      0 BMsRU
enp61s0f1        1500 16888513      0      0 0       6348080      0      0      0 BMsRU
ens3f0           9000        0      0      0 0       5992103      0      0      0 BMsRU
ens3f1           9000        0      0      0 0       5992111      0      0      0 BMsRU
ens6f0           9000        0      0      0 0       5992105      0      0      0 BMsRU
ens6f1           9000        0      0      0 0       5992093      0      0      0 BMsRU
lo              65536   798616      0      0 0        798616      0      0      0 LRU

 

2 nstat

nstat是一个简单的监视内核的SNMP计数器和网络接口状态的实用工具。

#kernel
IpInReceives                    71                 0.0
IpInDelivers                    71                 0.0
IpOutRequests                   41                 0.0
TcpActiveOpens                  3                  0.0
TcpInSegs                       56                 0.0
TcpOutSegs                      42                 0.0
TcpExtDelayedACKs               1                  0.0
TcpExtTCPPrequeued              3                  0.0
TcpExtTCPDirectCopyFromPrequeue 311                0.0
TcpExtTCPHPHits                 5                  0.0
TcpExtTCPHPHitsToUser           3                  0.0
TcpExtTCPPureAcks               8                  0.0
TcpExtTCPHPAcks                 22                 0.0
TcpExtTCPAutoCorking            1                  0.0
TcpExtTCPOrigDataSent           31                 0.0
IpExtInBcastPkts                15                 0.0
IpExtInOctets                   9148               0.0
IpExtOutOctets                  7201               0.0
IpExtInBcastOctets              5017               0.0
IpExtInNoECTPkts                71                 0.0

3 netstat

  netstat命令用于显示与IP、TCP、UDP和ICMP协议相关的统计数据。

netstat -i

Ip:
    5667465 total packets received
    0 forwarded
    0 incoming packets discarded
    5651164 incoming packets delivered
    3761237 requests sent out
    60 outgoing packets dropped
    31650 dropped because of missing route
Icmp:
    415130 ICMP messages received
    54 input ICMP message failed.
    ICMP input histogram:
        destination unreachable: 415121
        echo requests: 7
        echo replies: 2
    316 ICMP messages sent
    0 ICMP messages failed
    ICMP output histogram:
        destination unreachable: 307
        echo request: 2
        echo replies: 7
IcmpMsg:
        InType0: 2
        InType3: 415121
        InType8: 7
        OutType0: 7
        OutType3: 307
        OutType8: 2
Tcp:
    692475 active connections openings
    698 passive connection openings
    415666 failed connection attempts
    9 connection resets received
    1 connections established
    3461498 segments received
    3578535 segments send out
    288371 segments retransmited
    0 bad segments received.
    99 resets sent
Udp:
    5879 packets received
    200 packets to unknown port received.
    0 packet receive errors
    6088 packets sent
    0 receive buffer errors
    0 send buffer errors
UdpLite:
TcpExt:
    88 invalid SYN cookies received
    15156 TCP sockets finished time wait in slow timer
    11310 delayed acks sent
    180 delayed acks further delayed because of locked socket
    Quick ack mode was activated 30 times
    1504256 packets directly queued to recvmsg prequeue.
    11352010 bytes directly in process context from backlog
    1994852883 bytes directly received in process context from prequeue
    171448 packet headers predicted
    1577590 packets header predicted and directly queued to user
    627508 acknowledgments not containing data payload received
    481504 predicted acknowledgments
    4 congestion windows recovered without slow start after partial ack
    287605 other TCP timeouts
    9 connections reset due to early user close
    764 connections aborted due to timeout
    IPReversePathFilter: 716
    TCPRcvCoalesce: 40294
    TCPOFOQueue: 1476
    TCPSpuriousRtxHostQueues: 93
    TCPAutoCorking: 72967
    TCPSynRetrans: 288265
    TCPOrigDataSent: 1710137
    TCPHystartTrainDetect: 15
    TCPHystartTrainCwnd: 353
IpExt:
    InNoRoutes: 15585
    InBcastPkts: 1768457
    InOctets: 3218892710
    OutOctets: 630926470
    InBcastOctets: 619318853
    InNoECTPkts: 6182892

显示网络统计。

列出所有TCP与UDP端口。

netstat -tulnp

常常配合

 grep 查找

 wc -l  数量统计

来使用

4 cat /proc/net/dev

在Linux系统中，系统调用是操作系统提供给应用程序使用操作系统服务的重要接口，但同时也正是通过系统调用机制，操作系统屏蔽了用户直接访问系统内核的可能性。幸运的是Linux提供了LKM机制可以使我们在内核空间工作，在LKM机制中一个重要的组成部分就是proc伪文件系统，它为用户提供了动态操作Linux内核信息的接口，是除系统调用之外另一个重要的Linux内核空间与用户空间交换数据的途径。

Linux提供的LKM机制可以使我们通过proc伪文件系统来获取Linux内核信息，而通过proc/net/dev我们可以实时获取网络适配器及统计信息。

Inter-|   Receive                                                |  Transmit
 face |bytes    packets errs drop fifo frame compressed multicast|bytes    packets errs drop fifo colls carrier compressed
enp61s0f3:       0       0    0    0    0     0          0         0        0       0    0    0    0     0       0          0
bond0.154: 23769663570 83593670    0   13    0     0          0         0 60272263526 72633188    0    0    0     0       0          0
 bond1:  841179   13944    0    0    0     0          0         0 500072910 8335227    0    0    0     0       0          0
enp61s0f0: 65741012185 114223003    0    0    0     0          0        13 147224458885 652802887    0    0    0     0       0          0
bond0.199: 1056232010083 1222889472    0  191    0     0          0         0 229863482606 1164038349    0    0    0     0       0          0
enp61s0f2:       0       0    0    0    0     0          0         0        0       0    0    0    0     0       0          0
 bond0: 1102365185281 1360684498    0  305    0     0          0        26 293463920706 1288944846    0    0    0     0       0          0
    lo: 382521374129 913589064    0    0    0     0          0         0 382521374129 913589064    0    0    0     0       0          0
ens3f0:  498279    8229    0    0    0     0          0         0 333414500 5557589    0    0    0     0       0          0
ens6f0:  342900    5715    0    0    0     0          0         0 166658410 2777638    0    0    0     0       0          0
bond1.206:  383165    8231    0   13    0     0          0         0    99034    2329    0    0    0     0       0          0
 bond2:       0       0    0    0    0     0          0         0 333316136 5555266    0    0    0     0       0          0
enp61s0f1: 1036624173156 1246461496    0    0    0     0          0        13 146239461755 636141958    0    0    0     0       0          0
ens3f1:       0       0    0    0    0     0          0         0 166658456 2777638    0    0    0     0       0          0
ens6f1:       0       0    0    0    0     0          0         0 166657680 2777628    0    0    0     0       0          0
docker0:       0       0    0    0    0     0          0         0        0       0    0    0    0     0       0          0

参考链接（内有输出参数详解）：  https://www.cnblogs.com/zqyanywn/p/10024705.html