Solved Port number for built in Windows VPN

Hi folks.

For Windows's own built in VPN server any idea what port forwarding number should be defined in the router.

I have no trouble with a "Variable" IP address with the vpn server as I have a little batch program that sends me the current ip address of that machine -- with most fibre optic systems it seems that once booted the IP address changes very seldom anyway but the script is still useful.

E.g from the windows WSL run a bash command. (This is just to test the principle -- to run as a batch job say every 2 hours change the console input (read) to variables.

!/bin/bash
# Send email from bash
# simple script to send simple email with your IP address (external)

read -p "Enter SMTP email server address: " server
read -p "Enter SMTP Port: " port
read -p "Enter Your Email Address: " from
read -p "Enter Recipient's Email Address: " to
# get your public IP address
myip="$(dig +short myip.opendns.com @ReSolver1.opendns.com)"
# create message
function mail_input {
echo "ehlo $(hostname -f)"
echo "MAIL FROM: <$from>"
echo "RCPT TO: <$to>"
echo "DATA"
echo "From: <$from>"
echo "To: <$to>"
echo "Subject: Testing SMTP Mail"
echo " "
echo "Your public internet address is "
echo $myip
echo " "
echo "finished"
echo "."
echo "quit"
}

mail_input | netcat $server $port || err_exit

Don't forget to finish the inline text with the "." line before the SMTP quit command.

Using this method doesn't require the use of an email server or client on the host (you will need to read the email of course to see the content !!)


This should also render those programs like dyndns etc unnecessary too.

After this you have the ip address so you should be able to connect.

Probably you can run a similar script in windows -- netcat etc.

cheers
jimbo

According to this: Windows 10/11 VPN using a different port: is it possible?

1273 1723 - and cannot be changed.

johnlgalt said:

According to this: Windows 10/11 VPN using a different port: is it possible?

1273 - and cannot be changed.

Click to expand...

Typo? shouldn't it be port 1723?

SlicEnDicE said:

Typo? shouldn't it be port 1723?

Click to expand...

Lol yes, thank you, I definitely 'fat-fingered' that one!

Fixed!

Also GRE needs TCP/47, PPTP TCP/1723, L2TP UDP/1701, ISAKMP and CISCO etc... TCP-UDP/500 and UDP/4500 (IPSec)
Did I get all of them...

Yeah, I don't use the built-in one, so I didn't even consider looking at all the available options for protocols lol.

SlicEnDicE said:

Also GRE needs TCP/47, PPTP TCP/1723, L2TP UDP/1701, ISAKMP and CISCO etc... TCP-UDP/500 and UDP/4500 (IPSec)
Did I get all of them...

View attachment 55403

Click to expand...

No idea what any of that means

Thanks though 1723 works so marking problem as solved.

Tested it by using Mobile phone from 5G network to connect to the windows VPN.

"Alles in Ordnung" so marking as solved.

I know there are better more secure solutions but my primary goal was to get the wretched thing to work in the first place. After it's working is IMO the time to tighten up security and access, otherwise with some of this stuff nobody would ever get it working.

Cheers
jimbo