Linux中怎么检查本地开放端口列表

如何使用 Linux 命令 netstat 检查系统中的开放端口列表

它可以列出所有的 tcp、udp 连接和所有的 unix 套接字连接。 它用于发现发现网络问题，确定网络连接数量。

netstat -tplugnActive Internet connections (only servers)Proto Recv-Q Send-Q Local Address           Foreign Address         State       PID/Program nametcp        0      0 0.0.0.0:25              0.0.0.0:*               LISTEN      2038/mastertcp        0      0 127.0.0.1:199           0.0.0.0:*               LISTEN      1396/snmpdtcp        0      0 0.0.0.0:80              0.0.0.0:*               LISTEN      1398/Httpdtcp        0      0 0.0.0.0:22              0.0.0.0:*               LISTEN      1388/sshdtcp6       0      0 :::25                   :::*                    LISTEN      2038/mastertcp6       0      0 :::22                   :::*                    LISTEN      1388/sshdudp        0      0 0.0.0.0:39136           0.0.0.0:*                           1396/snmpdudp        0      0 0.0.0.0:56130           0.0.0.0:*                           1396/snmpdudp        0      0 0.0.0.0:40105           0.0.0.0:*                           1396/snmpdudp        0      0 0.0.0.0:11584           0.0.0.0:*                           1396/snmpdudp        0      0 0.0.0.0:30105           0.0.0.0:*                           1396/snmpdudp        0      0 0.0.0.0:50656           0.0.0.0:*                           1396/snmpdudp        0      0 0.0.0.0:1632            0.0.0.0:*                           1396/snmpdudp        0      0 0.0.0.0:28265           0.0.0.0:*                           1396/snmpdudp        0      0 0.0.0.0:40764           0.0.0.0:*                           1396/snmpdudp        0      0 10.90.56.21:123         0.0.0.0:*                           895/ntpdudp        0      0 127.0.0.1:123           0.0.0.0:*                           895/ntpdudp        0      0 0.0.0.0:123             0.0.0.0:*                           895/ntpdudp        0      0 0.0.0.0:53390           0.0.0.0:*                           1396/snmpdudp        0      0 0.0.0.0:161             0.0.0.0:*                           1396/snmpdudp6       0      0 :::123                  :::*                                895/ntpdIPv6/IPv4 Group MembershipsInterface       RefCnt Group--------------- ------ ---------------------lo              1      224.0.0.1eth0            1      224.0.0.1lo              1      ff02::1lo              1      ff01::1eth0            1      ff02::1eth0            1      ff01::1

你也可以使用下面的命令检查特定的端口。

# # netstat -tplugn | grep :22tcp        0      0 0.0.0.0:22              0.0.0.0:*               LISTEN      1388/sshdtcp6       0      0 :::22                   :::*                    LISTEN      1388/sshd

如何使用 Linux 命令 ss 检查系统中的开放端口列表？

ss 被用于转储套接字统计信息。它也可以显示类似netstat 的信息。相比其他工具它可以展示更多的 TCP 状态信息。

# ss -lntuNetid  State      Recv-Q Send-Q                     Local Address:Port                                    Peer Address:Portudp    UNCONN     0      0                                      *:39136                                              *:*udp    UNCONN     0      0                                      *:56130                                              *:*udp    UNCONN     0      0                                      *:40105                                              *:*udp    UNCONN     0      0                                      *:11584                                              *:*udp    UNCONN     0      0                                      *:30105                                              *:*udp    UNCONN     0      0                                      *:50656                                              *:*udp    UNCONN     0      0                                      *:1632                                               *:*udp    UNCONN     0      0                                      *:28265                                              *:*udp    UNCONN     0      0                                      *:40764                                              *:*udp    UNCONN     0      0                            10.90.56.21:123                                                *:*udp    UNCONN     0      0                              127.0.0.1:123                                                *:*udp    UNCONN     0      0                                      *:123                                                *:*udp    UNCONN     0      0                                      *:53390                                              *:*udp    UNCONN     0      0                                      *:161                                                *:*udp    UNCONN     0      0                                     :::123                                               :::*tcp    LISTEN     0      100                                    *:25                                                 *:*tcp    LISTEN     0      128                            127.0.0.1:199                                                *:*tcp    LISTEN     0      128                                    *:80                                                 *:*tcp    LISTEN     0      128                                    *:22                                                 *:*tcp    LISTEN     0      100                                   :::25                                                :::*tcp    LISTEN     0      128                                   :::22                                                :::*

你也可以使用下面的命令检查特定的端口。

# # ss -lntu | grep ':25'tcp    LISTEN     0      100       *:25                    *:*tcp    LISTEN     0      100      :::25                   :::*

如何使用 Linux 命令 nmap 检查系统中的开放端口列表？

虽然 Nmap 通常用于安全审计，但许多系统和网络管理员发现它对于日常工作也非常有用，例如网络资产清点、管理服务升级计划以及监控主机或服务正常运行时间。

nmap -sTU -O localhostStarting Nmap 6.40 ( http://nmap.org ) at 2019-03-20 09:57 CDTNmap scan report for localhost (127.0.0.1)Host is up (0.00028s latency).Other addresses for localhost (not scanned): 127.0.0.1Not shown: 1994 closed portsPORT    STATE SERVICE22/tcp  open  ssh25/tcp  open  smtp80/tcp  open  http199/tcp open  smux123/udp open  ntp161/udp open  snmpDevice type: general purposeRunning: Linux 3.XOS CPE: cpe:/o:linux:linux_kernel:3OS details: Linux 3.7 - 3.9Network Distance: 0 hopsOS detection perfORMed. Please report any incorrect results at http://nmap.org/submit/ .Nmap done: 1 IP address (1 host up) scanned in 1.93 seconds

你也可以使用下面的命令检查特定的端口。

nmap -sTU -O localhost | grep 123123/udp open  ntp

如何使用 Linux 命令 lsof 检查系统中的开放端口列表？

它向你显示系统上打开的文件列表以及打开它们的进程。还会向你显示与文件相关的其他信息。

# lsof -iCOMMAND   PID   USER   FD   TYPE  DEVICE SIZE/OFF node NAMEntpd      895    ntp   16u  IPv4   18481      0t0  UDP *:ntpntpd      895    ntp   17u  IPv6   18482      0t0  UDP *:ntpntpd      895    ntp   18u  IPv4   18487      0t0  UDP localhost:ntpntpd      895    ntp   20u  IPv4   23020      0t0  UDP Centos7.2daygeek.com:ntpsshd     1388   root    3u  IPv4   20065      0t0  TCP *:ssh (LISTEN)sshd     1388   root    4u  IPv6   20067      0t0  TCP *:ssh (LISTEN)snmpd    1396   root    6u  IPv4   22739      0t0  UDP *:snmpsnmpd    1396   root    7u  IPv4   22729      0t0  UDP *:40105snmpd    1396   root    8u  IPv4   22730      0t0  UDP *:50656snmpd    1396   root    9u  IPv4   22731      0t0  UDP *:pammratcsnmpd    1396   root   10u  IPv4   22732      0t0  UDP *:30105snmpd    1396   root   11u  IPv4   22733      0t0  UDP *:40764snmpd    1396   root   12u  IPv4   22734      0t0  UDP *:53390snmpd    1396   root   13u  IPv4   22735      0t0  UDP *:28265snmpd    1396   root   14u  IPv4   22736      0t0  UDP *:11584snmpd    1396   root   15u  IPv4   22737      0t0  UDP *:39136snmpd    1396   root   16u  IPv4   22738      0t0  UDP *:56130snmpd    1396   root   17u  IPv4   22740      0t0  TCP localhost:smux (LISTEN)httpd    1398   root    3u  IPv4   20337      0t0  TCP *:http (LISTEN)master   2038   root   13u  IPv4   21638      0t0  TCP *:smtp (LISTEN)master   2038   root   14u  IPv6   21639      0t0  TCP *:smtp (LISTEN)sshd     9052   root    3u  IPv4 1419955      0t0  TCP CentOS7.2daygeek.com:ssh->ubuntu18-04.2daygeek.com:11408 (ESTABLISHED)httpd   13371 apache    3u  IPv4   20337      0t0  TCP *:http (LISTEN)httpd   13372 apache    3u  IPv4   20337      0t0  TCP *:http (LISTEN)httpd   13373 apache    3u  IPv4   20337      0t0  TCP *:http (LISTEN)httpd   13374 apache    3u  IPv4   20337      0t0  TCP *:http (LISTEN)httpd   13375 apache    3u  IPv4   20337      0t0  TCP *:http (LISTEN)

你也可以使用下面的命令检查特定的端口。

# lsof -i:80COMMAND   PID   USER   FD   TYPE DEVICE SIZE/OFF NODE NAMEhttpd    1398   root    3u  IPv4  20337      0t0  TCP *:http (LISTEN)httpd   13371 apache    3u  IPv4  20337      0t0  TCP *:http (LISTEN)httpd   13372 apache    3u  IPv4  20337      0t0  TCP *:http (LISTEN)httpd   13373 apache    3u  IPv4  20337      0t0  TCP *:http (LISTEN)httpd   13374 apache    3u  IPv4  20337      0t0  TCP *:http (LISTEN)httpd   13375 apache    3u  IPv4  20337      0t0  TCP *:http (LISTEN)