mjhjmtu

I was learning to configure a Debian server and familiarising myself with the common command lines.

However, after executing the reboot command in SSH, my subsequent SSH connections were refused and I have total no access to the server.

I was able to ping the server. I attempted to reboot through the Google cloud interface too, however I was still unable to connect successfully.

Having this as a cloud server, I do not have any physical access to the server. The solution that I seem to see are to reconfigure the SSH settings which I can't without logging in.

What are the possible alternatives I have now or recreating a new instance is the only solution?

Your best bet is to create the key manually with the gcloud console:

thufir@mordor:~$ 
thufir@mordor:~$ gcloud compute config-ssh
WARNING: The private SSH key file for Google Compute Engine does not exist.
WARNING: You do not have an SSH key for Google Compute Engine.
WARNING: [/usr/bin/ssh-keygen] will be executed to generate a key.
Generating public/private rsa key pair.
Enter passphrase (empty for no passphrase): 
Enter same passphrase again: 
Your identification has been saved in /home/thufir/.ssh/google_compute_engine.
Your public key has been saved in /home/thufir/.ssh/google_compute_engine.pub.
The key fingerprint is:
SHA256:ioreurewiopruweoiprwe thufir@mordor
The key's randomart image is:
+---[RSA 2048]----+
.......
| |
| |
+----[SHA256]-----+

Updated [https://www.googleapis.com/compute/v1/projects/<project>].
You should now be able to use ssh/scp with your instances.
For example, try running:

 $ ssh <instance>.<location>.<project>

thufir@mordor:~$ 
thufir@mordor:~$ ssh <instance>.<location>.<project>
The authenticity of host 'compute.<####> (<ip address>)' can't be established.
ECDSA key fingerprint is SHA256:<fingerprint?>.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added 'compute.<####>' (ECDSA) to the list of known hosts.
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$ 
$ 
$ whoami
thufir
$ pwd
/home/thufir
$ exit
Connection to <ip address> closed.
thufir@mordor:~$ 

source:

https://askubuntu.com/questions/803908/

see also:

How do I append a SSH key with JSON for Google cloud compute VPS?

I think Google gives a quite a comprehensive list of solutions for troubleshooting SSH errors, please refer here.

IMO, you may have incorrectly set up SSH keys, or there are misconfigured iptables.

Good night, this has just happened cmg tbm, I think you should have already fixed or reconfigured your vps, but for those who face this problem, I was able to connect through port 443, after that, run nano command / etc / ssh / sshd_config and uncomment the line that has #Port 22, only take the #