How to find Port number of IP address?

We can find out 开发者_开发百科IP address of a domain name or URL. But how to find out Port number on which a domain name is hosted?

Unfortunately the standard DNS A-record (domain name to IP address) used by web-browsers to locate web-servers does not include a port number. Web-browsers use the URL protocol prefix (http://) to determine the port number (http = 80, https = 443, ftp = 21, etc.) unless the port number is specifically typed in the URL (for example "http://www.simpledns.com:5000" = port 5000).

Can I specify a TCP/IP port number for my web-server in DNS? (Other than the standard port 80)

Quite an old question, but might be helpful to somebody in need.

If you know the url,

1. open the chrome browser,
2. open developer tools in chrome ,
3. Put the url in search bar and hit enter
4. look in network tab, you will see the ip and port both

DNS server usually have a standard of ports used. But if it's different, you could try nmap and do a port scan like so:

> nmap 127.0.0.1

The port is usually fixed, for DNS it's 53.

If it is a normal then the port number is always 80 and may be written as http://www.somewhere.com:80 Though you don't need to specify it as :80 is the default of every web browser.

If the site chose to use something else then they are intending to hide from anything not sent by a "friendly" or linked to. Those ones usually show with https and their port number is unknown and decided by their admin.

If you choose to runn a port scanner trying every number nn from say 10000 to 30000 in https://something.somewhere.com:nn Then your isp or their antivirus will probably notice and disconnect you.

Use of the netstat -a command will give you a list of connections to your system/server where you are executing the command.

For example it will display as below, where 35070 is the port number

 TCP    10.144.0.159:**52121**    sd-s-fgh:35070   ESTABLISHED

Port numbers are defined by convention. HTTP servers generally listen on port 80, ssh servers listen on 22. But there are no requirements that they do.

 domain = self.env['ir.config_parameter'].get_param('web.base.url')

I got the hostname and port number using this.