In order to use our
DynDNS service (also known as DDNS), the ports required have to be released. In many cases, firewalls block access to the server / nas. You may use our
Port Scan in such a case in order to check which ports are blocked or released. Don't forget to release the ports in the router as well.
If you have created a DynDNS url in your pro user account, you will find one in the DynDNS url list Button , with which the port can be scanned.
Make sure that your computer is configured as a "public network", otherwise external access is not possible.
Note: You may scan the ports of your server or router, a port check (scanning) of other servers or hosts is blocked (impossible) due to security reasons. In order to prevent abuse, your IP address will be saved in our database. With the use of our scanner you are giving your express consent.
Here you find a list of standard ports:
To make sure that the ports are not blocked (without an open port it is NOT POSSIBLE to use a DynDNS service!), please perform a check of the required ports. When you insert your update url into your router, do not forget to edit the port & release. Our scanner can also be used to verify a port forwarding, so you will receive information about possible sources of error.
Port No. |
Program |
Application - Information |
UDP / TCP |
Port 21 |
FTP Server |
File Upload / Download FTP |
Yes / Yes |
Port 21 |
FTPES |
Encrypted Data Transfer |
Yes / Yes |
Port 22 |
SSH |
Secure Shell - Server Access |
Yes / Yes |
Port 23 |
Telnet |
Terminal Emulation |
Yes / Yes |
Port 25 |
SMTP Mail Server |
Mail Transfer |
- / Yes |
Port 80 |
Webserver - WWW |
HTTP - Webserver |
- / Yes |
Port 80 |
WebDAV |
Data Transfer |
- / Yes |
Port 8080 |
Webserver (old) |
HTTP - Webserver |
Yes / Yes |
Port 43 |
Whois Protocol |
Domain Data Query |
- / Yes |
Port 53 |
DNS (Domain Name System) |
DNS Requests |
Yes / Yes |
Port 79 |
Finger |
User Information |
- / Yes |
Port 110 |
Mail Server |
Mail Transfer |
Yes / Yes |
Port 115 |
SFTP |
Simple File Transfer Protocol |
- / Yes |
Port 139 |
NetBIOS |
Network Basic Input Output System |
Yes / Yes |
Port 143 |
IMAP |
Mailbox Administration |
- / Yes |
Port 443 |
HTTPS |
Encrypted Data Transfer - SSL |
- / Yes |
Port 443 |
WebDAV |
Encrypted Data Transfer |
- / Yes |
Port 465 |
SMTPS |
Encrypted Mail Transfer - SSL |
- / Yes |
Port 990 |
FTPS |
Encrypted Data Transfer |
Yes / Yes |
Port 1433 |
MSSQL |
Microsoft SQL Server (Database Management) |
- / Yes |
Port 2638 |
SQL |
Anywhere Database Server |
- / Yes |
Port 3051 |
Galaxy Server |
Gateway Ticketing Systems |
Yes / Yes |
Port 3306 |
MySQL Server |
Database Access |
Yes / Yes |
Port 3389 |
Windows Remote Desktop |
Remote Desktop Access |
Yes / Yes |
Port 5900 |
Real VNC |
Viewer Access |
Yes / Yes |
Port 51234 |
Teamspeak |
Communication - Conferences |
Yes / Yes |
Port 5421 |
Network |
Netsupport Manager |
Yes / Yes |
Port 5984 |
Couch DB |
Database Server |
Yes / Yes |
Port 6112 |
Warcraft III |
Game Software Hosting |
Yes / - |
If the port scan will be successful (port open), you can input your current IP address (you can find on the page
How is my IP address) + scanned port in the browser line and already reach directly externally your home server / nas / computer / IP cam. Sample input in the browser line: 000.00.00.00:80 (actual IP address: port). Thus, the prerequisites are created, with our DynDNS service to reach your Webserver statically externally ('s connectivity).