How can I prevent PasswordAuthentication?

[woncheol-kim]

Hi, I'm wondering how I can prevent PasswordAuthentication.

Of course, I can manually edit /etc/ssh/sshd_config but it requires to restart sshd.

And then I've tried to edit launch_ssh_cloudflared.py and launch_ssh.py but this does not help.

Can I just prevent PasswordAuthentication when running init_git_cloudflared ?

[WassimBenzarti]

Hello @woncheol-kim,
Sorry for the late answer. Could you please explain further more what you mean by preventing PasswordAuthentication?

Is this what colab-ssh does by default when you execute the git_init_cloudflared ?

[woncheol-kim]

Dear @WassimBenzarti,

I've noticed that the init_git_cloudflared includes commands below:

echo 'PermitRootLogin yes' >> /etc/ssh/sshd_config
echo 'PasswordAuthentication yes' >> /etc/ssh/sshd_config

At first I had wanted to modify the script, but after frustration, I eventually solved the issue by executing following commands before init_git_cloudflared:

!echo 'PasswordAuthentication no' >> /etc/ssh/sshd_config
!echo 'ChallengeResponseAuthentication no' >> /etc/ssh/sshd_config

As the result the sshd_config looks like this:

PasswordAuthentication no
ChallengeResponseAuthentication no
PermitRootLogin yes
PasswordAuthentication yes

And the last line 'PasswordAuthentication yes' is ignored because of the first line.

[WassimBenzarti]

Thank you that's really helpful! We will make sure that we take into consideration these issues in later versions :)

[Brothergrin]

Dear WassimBenzarti, will you make a video tutorial for newcommers? It will be really helpful. Thanks if you will find time for that.