View port usage in Linux

-Bash-3.00 # netstat-TLN

 

 

The netstat-TLN command is used to view Linux port usage.

/Etc/init. d/vsftp start is used to start the ftp port ~!

View files/etc/services

Netstat

View the connected service port (established)

Netstat-

View All service ports (Listen, established)

Sudo netstat-AP

View All service ports and display corresponding servicesProgramName

NMAP <scan type> <scan parameters>

For example:

NMAP localhost

NMAP-P 1024-65535 localhost

NMAP-Pt 192.168.1.127-245

When we use netstat-APN to view network connections, we will find a lot similar to the following:

PROTO Recv-Q send-Q local address foreign address State PID/program name

TCP 0 52 218.104.81.152: 7710 211.100.39.250: 29488 established 6111/1

It indicates that port 7710 is opened on this server. Which program does this port belong? We can use the lsof-I: 7710 command to query:

Command PID user FD type device size node name

Sshd 1990 root 3u IPv4 4836 tcp *: 7710 (Listen)

In this way, we know that port 7710 belongs to the sshd program.