Firewall commonly required open ports

The following ports are commonly open in server boxes

• 21: ftp
• 22: ssh
• 23: telnet
• 25: smtp
• 80: http
• 110: pop3
• 137upp, 138udp, 139tcp, 445tcp: Samba
  
• 443: https
• 873: rsync
• 995: pop3 over ssl
  
• 2049: NFS
  
• 3306: mysql
• 5900: vnc
• 5901: xvnc
• 10000: webmin