Stupid question (?); are ports open on public and private ip the same?

[Helpful Tech Witch]

Its pretty simple. According to online port checking tools, port 25565 is open on my public ip. But, when I input my private ip, they don't have that port opened.

If a port is open on the public ip, is it openon the private one too?

 

 

 

 

also, should every port I try like 25, 80, 443, and 8912 are all closed, though they seem to be common ports like mail, http, https, and windows backup?

[Eigenvektor]

5 minutes ago, HelpfulTechWizard said:

Its pretty simple. According to online port checking tools, port 25565 is open on my public ip. But, when I input my private ip, they don't have that port opened.

If a port is open on the public ip, is it openon the private one too?

If you start a program and it listens on a port, you can typically tell it which interface it should bind to. On Linux you would typically configure something like "127.0.0.1" to make it listen only on your local network or "0.0.0.0" to listen on every interface.

 

Quote

also, should every port I try like 25, 80, 443, and 8912 are all closed, though they seem to be common ports like mail, http, https, and windows backup?

Yes, those ports should be closed, unless you're running a mail or web server. As a client you don't need these ports to be opened.

 

If you connect to a site like linustechtips.com, your browser will connect to the well-known ports 80 or 443 that are open on the server. The client port on your end is chosen at random and does not need to be open for incoming traffic.

[Helpful Tech Witch]

23 minutes ago, Eigenvektor said:

If you start a program and it listens on a port, you can typically tell it which interface it should bind to. On Linux you would typically configure something like "127.0.0.1" to make it listen only on your local network or "0.0.0.0" to listen on every interface.

 

Yes, those ports should be closed, unless you're running a mail or web server. As a client you don't need these ports to be opened.

 

If you connect to a site like linustechtips.com, your browser will connect to the well-known ports 80 or 443 that are open on the server. The client port on your end is chosen at random and does not need to be open for incoming traffic.

oh, that makes me think

 

and make me confuse on something else.....

[Vishera]

Private and public networks are separate,which applies to ports as well.

[Helpful Tech Witch]

Just now, Vishera said:

Private and public networks are separate,which applies to ports as well.

so how my private be the one with port 25565 forwarded, but it not be open on private (from what i can tell)

and my public not be forwarded, but have it open (as far as i can tell?)

never mind. for ip 192.168.xx.xxx its internal and external at 25565

[Vishera]

1 minute ago, HelpfulTechWizard said:

never mind. for ip 192.168.xx.xxx its internal and external at 25565

So the port is open on both the local network and the internet?

[Helpful Tech Witch]

Just now, Vishera said:

So the port is open on both the local network and the internet?

maybe. according to https://www.yougetsignal.com/tools/open-ports/ its only on my public not private ip (192.168.xx.xxx), though, like i said, the public ip (162.255.xx.xxx) isnt the one that the port is forwarded, its my private ip (192.168.xx.xxx).

[Vishera]

13 minutes ago, HelpfulTechWizard said:

maybe. according to https://www.yougetsignal.com/tools/open-ports/ its only on my public not private ip (192.168.xx.xxx), though, like i said, the public ip (162.255.xx.xxx) isnt the one that the port is forwarded, its my private ip (192.168.xx.xxx).

With this tool you cannot check if ports are open on the local network,since this tool has no access to your local network.

(The tool  - on the internet | Your local network - separated from the internet)

[Eigenvektor]

6 hours ago, HelpfulTechWizard said:

maybe. according to https://www.yougetsignal.com/tools/open-ports/ its only on my public not private ip (192.168.xx.xxx), though, like i said, the public ip (162.255.xx.xxx) isnt the one that the port is forwarded, its my private ip (192.168.xx.xxx).

As @Vishera said, you can't use that tool to check your private IP. It is, as the name says, private. Connections to and from IP addresses in the private range(s) are never routed over the internet. This would lead to all kinds of chaos, since 192.168.x.x is the IP used by most people for their internal network, so it would not be unique.

 

You could use a tool like "nmap" to scan your PC for open ports from another PC, on the same network.