On Sat, Jan 13, 2024 at 09:02:16PM +0000, ael via Dng wrote:
>
> But now when the debian machines (1 & 2) "ssh -X" into the daedalus box
> (machine3) the X11 forwarding is not working.

I have [partially] solved the problem in the last few minutes.

The sshd_config man page notes that
X11UseLocalhost yes
uses the loopback address.

I checked with
ifconfig lo
on the devuan machine (I should probably used ss) and found that it had
no inet address or netmask and so on.

ifup lo
fixed that.

I restarted the devuan sshd with
X11UseLocalhost yes
and now ssh -X is working properly.

That does not explain why
auto lo
iface lo inet loopback
in /etc/network/interfaces
did not work.

Nor does it explain the failure with
X11UseLocalhost no

But at least things are working now. I can look at those other problems
later. I hope that this might be useful to anyone else who hits this
sort of problem.

ael