Solved localhost vs. 127.0.0.1 with Microsoft’s sshd

Baeolophus

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• Wednesday at 7:13 PM

• #1

When I install Microsoft’s sshd (Settings → System → Optional features), I can make ssh connections to that host. So far, so good!

I would like to empty a command like

Bash:

ssh user@windowshost -L 15900:localhost:5900

. This is supposed to allow me to make a VNC connection on Port 15900 on the host from where the ssh connection originates, with the ssh connection forwarding that VNC traffic to Port 5900 on the host being connected to (windowshost), which is localhost to itself. This does not work. What does work is:

Bash:

ssh user@windowshost -L 15900:127.0.0.1:5900

It‘s as though the Windows shell does not understand “localhost.”

What is going on?

 

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Levitate11

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• Wednesday at 9:56 PM

• #2

Just as a base test, can you ping localhost?

 

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Baeolophus

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• Thursday at 10:28 AM

• #3

Here’s what it looks like:


In a shell made accessible via ssh, ping to 127.0.0.1 and localhost both work. However, whatever evaluates the

Bash:

-L local_socket:host:hostport

argument to my local bash shell ssh command on the remote host, which is a Windows 11 PC, does not know what to do, if host is “localhost.”

 

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telepro21

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• Yesterday at 9:40 AM

• #4

Back in the day, it was sometimes necessary to edit the native Hosts file on a particular Windows PC to direct certain traffic where you want it to go. This article may offer some assistance--> How to Edit Hosts File in Windows 11: A Step-by-Step Guide - Solve Your Tech

 

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garlin

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• Yesterday at 10:41 AM

• #5

For your PC, localhost is returned as a IPv6 address [::1]

Your options would be:

- Disable IPv6 on the network adapter's properties, if you don't need IPv6​

- Figure out how to configure IPv6 port forwarding​

- Use the 127.0.0.1 address to force IPv4 mode​

 

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Baeolophus

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• Yesterday at 2:02 PM

• #6

garlin said:

For your PC, localhost is returned as a IPv6 address [::1]

Click to expand...

That’s the answer! How do I turn off IPv6 on a Windows machine?

 

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pseymour

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• Yesterday at 2:05 PM

• #7

Configure IPv6 for advanced users - Windows Server

Provides step-by-step guidance for how to use the Windows registry to disable IPv6 or certain IPv6 components in Windows.

learn.microsoft.com

I normally set mine to 0x20, to prefer IPv4 without turning off v6.

 

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Baeolophus

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• Yesterday at 2:05 PM

• #8

Never mind! This seems to be a good set of instructions: Windows Central—How to disable TCP/IPv6 (IPv6) on Windows 11.

 

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