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,
- open the chrome browser,
- open developer tools in chrome ,
- Put the url in search bar and hit enter
- 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.
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