We can find out 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.
Related
i know there are lots of similar questions about but no one help me.
I have a linux server running nginx reverse proxy in docker, a duckdns domain created,opened my router port 80 and 443. I can't access from outside with my domain name or public ip, it seems like my router refuses external request. I tried with lots of configuration, follow lots of guides on web... I get crazy to solve this problem.
I think problem is before nginx, so i not post my nginx conf. If can help, I will post it.
Hope someone can help me. Thank you so much
There are several things that could be causing the issue with your router refusing external requests. Here are a few things to check:
Make sure that your router's firewall is configured to allow incoming connections on ports 80 and 443. Some routers have a built-in firewall that needs to be configured to allow traffic through specific ports.
Confirm that your router is properly forwarding incoming requests to the correct IP address and port on your network. This is typically done through a feature called port forwarding.
Check your router's security settings to ensure that it is not blocking incoming requests based on the source IP address or domain name. Some routers have the option to block incoming requests from specific IP addresses or domain names.
Confirm that your Linux server is properly configured to handle incoming requests. This includes checking that your Nginx reverse proxy is running and properly configured to forward requests to the correct IP address and port.
Verify that your DNS is pointing to the right IP address, you can use online tools like https://www.whatsmydns.net/ to check this.
Check if your router have any VPN or proxy service enabled, which could be affecting the incoming request.
Check if your ISP is blocking incoming connection to your public IP address.
It's also possible that there might be a problem with your router's firmware or hardware, in that case, you may need to contact the manufacturer for further assistance.
I'm trying to connect to my public IP http://34.125.119.106:8080/, where I have a Jenkins service running but I can't and don't know why.
I've create firewall rule to allow tcp traffic on port 8080, which is the port exposed to Jenkins, but I still cannot connect. I looked into the /etc/default/jenkins file, to see if everything inside was configured correctly. I tried to line in this file like 'HTTP_HOST=127.0.0.1', like some people advise to do ,but it doesn't work for my case. Does anyone know how to solve this?
Sorry for my bad English.
enter image description here
i made a test and it successfully connected,but i still cant connect to my external Ip
Use the default settings, because HTTP_HOST=127.0.0.1 locks you out:
HTTP_HOST=0.0.0.0
HTTP_PORT=8080
HTTPS_HOST=0.0.0.0
HTTPS_PORT=443
Listing to all interfaces with 0.0.0.0 is fine, but HTTP_PORT should be -1.
As a first step my recommendation is to check if your service is exposed and through what port number. For this you can use command sudo netstat -plntu. You should be looking for an output similar to:
tcp6 0 0 :::8080 :::* LISTEN 17917/java
If its not, change your /etc/default/jenkins file to port 8080
After that from inside your GCP project, you can run a connectivity test having as source one of the IP addresses you are using to reach your Server and as destination your Servers VM instance IP address. This test will simulate traffic and tell you where it's getting stuck whether if it's stuck on the way to your Server or if your server is not correctly configured. You can get a good reference in this document.
If you have already configured your ingress firewall rule, just make sure its applied to your VM, it sometimes happens that you have a network tag on your VM instance and another tag on your firewall rule.
I'm trying to use UPnP to open a port, so I'm experimenting with miniupnpc. I've observed a handful of people use and suggest upnpc -a <internal ip> <internal port> <external port> <protocol> to open the specified external port and point it to the application running on the specified internal port.
Before I continue, I will note that UPnP is on in my router's settings, and that it lists a few connections, though when I check them with a port checker I find that none of them are actually working? Or at least none of them seem to be open.
When I try to map the internal port 5000 to the external port 7777 with the following command:
upnpc -a 192.168.1.10 5000 7777 tcp
What I find is that it "works" without any explicit errors, but
the external ip it maps to isn't really an external ip at all. Here's the output following the command given above:
upnpc : miniupnpc library test client, version 2.1.
(c) 2005-2019 Thomas Bernard.
Go to http://miniupnp.free.fr/ or https://miniupnp.tuxfamily.org/
for more information.
List of UPNP devices found on the network :
desc: http://192.168.1.1:5000/Public_UPNP_gatedesc.xml
st: urn:schemas-upnp-org:device:InternetGatewayDevice:1
Found a (not connected?) IGD : http://192.168.1.1:5000/Public_UPNP_C3
Trying to continue anyway
Local LAN ip address : 192.168.1.10
ExternalIPAddress = 192.168.0.153
InternalIP:Port = 192.168.1.10:5000
external 192.168.0.153:7777 TCP is redirected to internal 192.168.1.10:5000 (duration=0)
Obviously, 192.168.0.153 is not an external IP Address, and yet it seems to be treating it as though it is. Why might this be?
EDIT: Upon further inspection, it seems like since I have a multi-router set up, the "external ip" here is actually the internal ip of the secondary router. I wonder why this is, though, and whether it can be circumvented.
I have setup the Swann DVR Surveillance System. I am able to access the web client at 192.168.1.99:85 (static ip in internal LAN). I have port forwarded 85 packets to 192.168.1.99. But when I access my external ip eg xxx.xxx.xxx.xxx:85 I get unable to connect error.
I checked if the port is open in an online tool and it says port 85 is open. HEre is my port forwarding page:
Please Help me. Thanks in advance
EDIT: I have tried changing ports to 89, 9001, 8080 and no luck..
Ive finally figured out what I was doing wrong from a friend. It seems there is something called NAT Loopback (https://en.wikipedia.org/wiki/Network_address_translation#NAT_loopback) that allows you to access your public IP address from within your own network. Most routers have this feature disabled by default. And hence whenever you try to access your IP address the packets are dropped and you get the Host Unreachable ICMP packet.
Anyway to use this try to enable NAT Reflection or NAT Loopback on your router.
If you dont have that feature, you can test your system from outside the network and itll work just fine. Sorry for not reporting the answer sooner.
Yeah, same problem. As Steve Robinson said, you cannot always access your public IP from your NAT. Try running Apache and use your phone (turn off WiFi and turn on mobile data) to test if this is the case.
I implemented red5phone with asterisk as external sip proxy. I tried to connect with 2 clients and there's definitely a different IP. When I saw at asterisk by using the sip show peers cli command, it displayed like this :
Name/username Host Dyn Nat ACL Port Status
1001/1001 10.151.32.26 D N 38841 OK (173 ms)
1000/1000 10.151.32.26 D 5060 OK (17 ms)
The host IP is the same, although it's a different client.
Can somebody explain this? Is it an error?
Is that IP address the IP address of the red5 server? Perhaps your red5 server is not passing the client IP addresses but its own to Asterisk?
it's your proxy ip address and that's fine because each user is identified by port number which is different