Linux command to check the number connections to port 

In this tutorial, I will explain how to check the number of connections to port using linux command.

check the number of connections to database

Command :netstat -antp | grep :3306 | wc -l  

//3306 is Mysql port Number

check the number of connections to FTP



Command :netstat -antp | grep :21 | wc -l  

//21 is FTP port number

Linux command to check the number connections to port

Some Important Linux Port Numbers:

21 => FTP
443 =>HTTP Secure
22 => SSH
23 = >  Telnet
2086 = >  CPANEL WHM
2087 = > CPANEL WHM - Secure/SSL
2095 = >  cpanel webmail
111 = >  rpcbind
953 = > rndc
143 = > IMAP Protocol
993 = > IMAP Secure
3306 =  > MysQL Server
4643 = >  Virtuosso Power Panel

2082 = >  CPANEL
2083 = >  CPANEL - Secure/SSL
Plesk Control Panel = >  8443
DirectAdmin Control Panel = >  2222
Webmin Control Panel = >  10000
2096 = >  cpanel webmail - secure/SSL
25 = > SMTP Mail Transfer
43 = >  WHOIS service
53 = >  name server (DNS)
80 = >  HTTP (Web server)
110 = >  POP protocol (for email)
995 = > POP over SSL/TLS
9999 = >  Urchin