本文转自:http://www.cnblogs.com/peida/archive/2013/03/11/2953420.html

ss是Socket Statistics的缩写。顾名思义,ss命令可以用来获取socket统计信息,它可以显示和netstat类似的内容。但ss的优势在于它能够显示更多更详细的有关TCP和连接状态的信息,而且比netstat更快速更高效。

当服务器的socket连接数量变得非常大时,无论是使用netstat命令还是直接cat /proc/net/tcp,执行速度都会很慢。可能你不会有切身的感受,但请相信我,当服务器维持的连接达到上万个的时候,使用netstat等于浪费 生命,而用ss才是节省时间。

天下武功唯快不破。ss快的秘诀在于,它利用到了TCP协议栈中tcp_diag。tcp_diag是一个用于分析统计的模块,可以获得Linux 内核中第一手的信息,这就确保了ss的快捷高效。当然,如果你的系统中没有tcp_diag,ss也可以正常运行,只是效率会变得稍慢。(但仍然比 netstat要快。)

1.命令格式:

ss [参数]

ss [参数] [过滤]

2.命令功能:

ss(Socket Statistics的缩写)命令可以用来获取 socket统计信息,此命令输出的结果类似于 netstat输出的内容,但它能显示更多更详细的 TCP连接状态的信息,且比 netstat 更快速高效。它使用了 TCP协议栈中 tcp_diag(是一个用于分析统计的模块),能直接从获得第一手内核信息,这就使得 ss命令快捷高效。在没有 tcp_diag,ss也可以正常运行。

3.命令参数:

-h, –help 帮助信息

-V, –version 程序版本信息

-n, –numeric 不解析服务名称

-r, –resolve        解析主机名

-a, –all 显示所有套接字(sockets)

-l, –listening 显示监听状态的套接字(sockets)

-o, –options        显示计时器信息

-e, –extended       显示详细的套接字(sockets)信息

-m, –memory         显示套接字(socket)的内存使用情况

-p, –processes 显示使用套接字(socket)的进程

-i, –info 显示 TCP内部信息

-s, –summary 显示套接字(socket)使用概况

-4, –ipv4           仅显示IPv4的套接字(sockets)

-6, –ipv6           仅显示IPv6的套接字(sockets)

-0, –packet         显示 PACKET 套接字(socket)

-t, –tcp 仅显示 TCP套接字(sockets)

-u, –udp 仅显示 UCP套接字(sockets)

-d, –dccp 仅显示 DCCP套接字(sockets)

-w, –raw 仅显示 RAW套接字(sockets)

-x, –unix 仅显示 Unix套接字(sockets)

-f, –family=FAMILY  显示 FAMILY类型的套接字(sockets),FAMILY可选,支持  unix, inet, inet6, link, netlink

-A, –query=QUERY, –socket=QUERY

QUERY := {all|inet|tcp|udp|raw|unix|packet|netlink}[,QUERY]

-D, –diag=FILE     将原始TCP套接字(sockets)信息转储到文件

-F, –filter=FILE   从文件中都去过滤器信息

FILTER := [ state TCP-STATE ] [ EXPRESSION ]

 

4.使用实例:

实例1:显示TCP连接

命令:

ss -t -a

输出:

 

复制代码
[root@localhost ~]# ss -t -a
State      Recv-Q Send-Q                                Local Address:Port                                    Peer Address:Port
LISTEN     0      0                                         127.0.0.1:smux                                               *:*
LISTEN     0      0                                                 *:3690                                               *:*
LISTEN     0      0                                                 *:ssh                                                *:*
ESTAB      0      0                                   192.168.120.204:ssh                                        10.2.0.68:49368
[root@localhost ~]# 
复制代码

说明:

 

实例2:显示 Sockets 摘要

命令:

ss -s

输出:

 

复制代码
[root@localhost ~]# ss -s
Total: 34 (kernel 48)
TCP:   4 (estab 1, closed 0, orphaned 0, synrecv 0, timewait 0/0), ports 3

Transport Total     IP        IPv6
*         48        –         –
RAW       0         0         0
UDP       5         5         0
TCP       4         4         0
INET      9         9         0
FRAG      0         0         0

[root@localhost ~]# 

复制代码

说明:

列出当前的established, closed, orphaned and waiting TCP sockets

 

实例3:列出所有打开的网络连接端口

命令:

ss -l

输出:

 

复制代码
[root@localhost ~]# ss -l
Recv-Q Send-Q                                     Local Address:Port                                         Peer Address:Port
0      0                                              127.0.0.1:smux                                                    *:*
0      0                                                      *:3690                                                    *:*
0      0                                                      *:ssh                                                     *:*
[root@localhost ~]# 
复制代码

说明:

 

实例4:查看进程使用的socket

命令:

ss -pl

输出:

 

复制代码
[root@localhost ~]# ss -pl
Recv-Q Send-Q                                     Local Address:Port                                         Peer Address:Port
0      0                                              127.0.0.1:smux                                                    *:*        users:((snmpd,2716,8))
0      0                                                      *:3690                                                    *:*        users:((svnserve,3590,3))
0      0                                                      *:ssh                                                     *:*        users:((sshd,2735,3))
[root@localhost ~]#
复制代码

说明:

 

实例5:找出打开套接字/端口应用程序

命令:

ss -lp | grep 3306

输出:

 

复制代码
[root@localhost ~]# ss -lp|grep 1935
0      0                            *:1935                          *:*        users:((fmsedge,2913,18))
0      0                    127.0.0.1:19350                         *:*        users:((fmsedge,2913,17))
[root@localhost ~]# ss -lp|grep 3306
0      0                            *:3306                          *:*        users:((mysqld,2871,10))
[root@localhost ~]# 
复制代码

说明:

 

实例6:显示所有UDP Sockets

命令:

ss -u -a

输出:

 

复制代码
[root@localhost ~]# ss -u -a
State      Recv-Q Send-Q                                Local Address:Port                                    Peer Address:Port
UNCONN     0      0                                         127.0.0.1:syslog                                             *:*
UNCONN     0      0                                                 *:snmp                                               *:*
ESTAB      0      0                                   192.168.120.203:39641                                  10.58.119.119:domain
[root@localhost ~]#
复制代码

说明:

 

实例7:显示所有状态为established的SMTP连接

命令:

ss -o state established ‘( dport = :smtp or sport = :smtp )’

输出:

 

[root@localhost ~]# ss -o state established ‘( dport = :smtp or sport = :smtp )’ 
Recv-Q Send-Q                                     Local Address:Port                                         Peer Address:Port
[root@localhost ~]#

说明:

 

实例8:显示所有状态为Established的HTTP连接

命令:

ss -o state established ‘( dport = :http or sport = :http )’

输出:

 

[root@localhost ~]# ss -o state established ‘( dport = :http or sport = :http )’ 
Recv-Q Send-Q                                     Local Address:Port                                         Peer Address:Port
0      0                                              75.126.153.214:2164                                        192.168.10.42:http
[root@localhost ~]# 

说明:

 

实例9:列举出处于 FIN-WAIT-1状态的源端口为 80或者 443,目标网络为 193.233.7/24所有 tcp套接字

命令:

ss -o state fin-wait-1 ‘( sport = :http or sport = :https )’ dst 193.233.7/24

输出:

说明:

 

实例10:用TCP 状态过滤Sockets:

命令:

ss -4 state FILTER-NAME-HERE

ss -6 state FILTER-NAME-HERE

输出:

[root@localhost ~]#ss -4 state closing 
Recv-Q Send-Q                                                  Local Address:Port                                                      Peer Address:Port
1      11094                                                  75.126.153.214:http                                                      192.168.10.42:4669

 

说明:

FILTER-NAME-HERE 可以代表以下任何一个:

established

syn-sent

syn-recv

fin-wait-1

fin-wait-2

time-wait

closed

close-wait

last-ack

listen

closing

 

all : 所有以上状态

connected : 除了listen and closed的所有状态

synchronized :所有已连接的状态除了syn-sent

bucket : 显示状态为maintained as minisockets,如:time-wait和syn-recv.

big : 和bucket相反.

 

实例11:匹配远程地址和端口号

命令:

ss dst ADDRESS_PATTERN

ss dst 192.168.1.5

ss dst 192.168.119.113:http

ss dst 192.168.119.113:smtp

ss dst 192.168.119.113:443

输出:

 

复制代码
[root@localhost ~]# ss dst 192.168.119.113
State      Recv-Q Send-Q                                Local Address:Port                                    Peer Address:Port
ESTAB      0      0                                   192.168.119.103:16014                                192.168.119.113:20229
ESTAB      0      0                                   192.168.119.103:16014                                192.168.119.113:61056
ESTAB      0      0                                   192.168.119.103:16014                                192.168.119.113:61623
ESTAB      0      0                                   192.168.119.103:16014                                192.168.119.113:60924
ESTAB      0      0                                   192.168.119.103:16050                                192.168.119.113:43701
ESTAB      0      0                                   192.168.119.103:16073                                192.168.119.113:32930
ESTAB      0      0                                   192.168.119.103:16073                                192.168.119.113:49318
ESTAB      0      0                                   192.168.119.103:16014                                192.168.119.113:3844
[root@localhost ~]# ss dst 192.168.119.113:http
State      Recv-Q Send-Q                                Local Address:Port                                    Peer Address:Port
[root@localhost ~]# ss dst 192.168.119.113:3844
State      Recv-Q Send-Q                                Local Address:Port                                    Peer Address:Port
ESTAB      0      0                                   192.168.119.103:16014                                192.168.119.113:3844
[root@localhost ~]# 
复制代码

说明:

 

实例12:匹配本地地址和端口号

命令:

ss src ADDRESS_PATTERN

ss src 192.168.119.103

ss src 192.168.119.103:http

ss src 192.168.119.103:80

ss src 192.168.119.103:smtp

ss src 192.168.119.103:25

输出:

 

复制代码
[root@localhost ~]# ss src 192.168.119.103:16021
State      Recv-Q Send-Q                                Local Address:Port                                    Peer Address:Port
ESTAB      0      0                                   192.168.119.103:16021                                192.168.119.201:63054
ESTAB      0      0                                   192.168.119.103:16021                                192.168.119.201:62894
ESTAB      0      0                                   192.168.119.103:16021                                192.168.119.201:63055
ESTAB      0      0                                   192.168.119.103:16021                                192.168.119.201:2274
ESTAB      0      0                                   192.168.119.103:16021                                192.168.119.201:44784
ESTAB      0      0                                   192.168.119.103:16021                                192.168.119.201:7233
ESTAB      0      0                                   192.168.119.103:16021                                192.168.119.103:58660
ESTAB      0      0                                   192.168.119.103:16021                                192.168.119.201:44822
ESTAB      0      0                                   192.168.119.103:16021                                     10.2.1.206:56737
ESTAB      0      0                                   192.168.119.103:16021                                     10.2.1.206:57487
ESTAB      0      0                                   192.168.119.103:16021                                     10.2.1.206:56736
ESTAB      0      0                                   192.168.119.103:16021                                     10.2.1.206:64652
ESTAB      0      0                                   192.168.119.103:16021                                     10.2.1.206:56586
ESTAB      0      0                                   192.168.119.103:16021                                     10.2.1.206:64653
ESTAB      0      0                                   192.168.119.103:16021                                     10.2.1.206:56587
[root@localhost ~]# 
复制代码

说明:

 

实例13:将本地或者远程端口和一个数比较

命令:

ss dport OP PORT

ss sport OP PORT

输出:

复制代码

[root@localhost ~]# ss  sport = :http 
[root@localhost ~]# ss  dport = :http 
[root@localhost ~]# ss  dport \> :1024 
[root@localhost ~]# ss  sport \> :1024 
[root@localhost ~]# ss sport \< :32000 
[root@localhost ~]# ss  sport eq :22 
[root@localhost ~]# ss  dport != :22 
[root@localhost ~]# ss  state connected sport = :http 
[root@localhost ~]# ss \( sport = :http or sport = :https \) 
[root@localhost ~]# ss -o state fin-wait-1 \( sport = :http or sport = :https \) dst 192.168.1/24

复制代码

说明:

ss dport OP PORT 远程端口和一个数比较;ss sport OP PORT 本地端口和一个数比较。

OP 可以代表以下任意一个:

<= or le : 小于或等于端口号

>= or ge : 大于或等于端口号

== or eq : 等于端口号

!= or ne : 不等于端口号

< or gt : 小于端口号

> or lt : 大于端口号

 

实例14:ss 和 netstat 效率对比

命令:

time netstat -at

time ss

输出:

 

复制代码
[root@localhost ~]# time ss   
real    0m0.739s
user    0m0.019s
sys     0m0.013s
[root@localhost ~]# 
[root@localhost ~]# time netstat -at
real    2m45.907s
user    0m0.063s
sys     0m0.067s
[root@localhost ~]#
复制代码

 

说明:

用time 命令分别获取通过netstat和ss命令获取程序和概要占用资源所使用的时间。在服务器连接数比较多的时候,netstat的效率完全没法和ss比。