I would test port status with
nmap -P0 -p 22 <remote server public IP>
You want the response to be "open"
Bruce
On 5/28/19 12:17 PM, Gary Dale wrote:
I'm running Debian/Testing on an AMD64 machine.
I follow what I believe is a fairly conventional way of connecting to
remote machines. Firstly I establish an SSH tunnel using a command like:
ssh <remote server public IP> -L 5902:<remote workstation local
IP>:5900
where the remote server public IP is that of the router (DD-WRT) with
port 22 forwarded to the local IP of a remote Debian/Stable server.
The remote workstation IPs are in the 192.168.1.* range. The SSH
connection works fine.
Then I connect to localhost:5902 using a VNC viewer (tried a few).
I've been doing this for a decade with no significant problems.
However I haven't been able to do this since at least yesterday
(previous remote login was a week ago. It worked). No matter which
remote machine I try to connect to, I never get to the password
prompt. Instead the connection attempt eventually attempt times out.
I can log onto a KVM virtual machine running on the remote server
using the Virtual Machine Manager GUI. From there I can connect to the
other (real) machines using the Tight VNC viewer.
Since I can connect to the remote workstations from the VM, the
problem cannot be with their service setup. And since the problem
isn't resolved by using a different VNC viewer from my local
workstation, the problem can't be the VNC client. This just leaves the
ssh tunnel - specifically the port forwarding - as the only common
element.