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This is a question regarding the OpenSSH client on Linux, MacOSX and FreeBSD.

Normally, I log into systems using my SSH key.

Occasionally, I want my SSH client to ignore my SSH key and use a password instead. If I 'ssh hostname', my client prompts me for the Passphrase to my SSH key which is an annoyance. Instead, I want the client to simply ignore my SSH key, so that the server will ask me for my password instead.

I tried the following, but I am still prompted for the passphrase to my SSH key. After this, I am prompted for my password.

ssh -o PreferredAuthentications=password host.example.org

I want to do this on the client side, without any modification of the remote host.

7ochem
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Stefan Lasiewski
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2 Answers2

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Try ssh -o PasswordAuthentication=yes -o PreferredAuthentications=keyboard-interactive,password -o PubkeyAuthentication=no host.example.org

In ssh v2, keyboard-interactive is another way to say "password". The -o PubkeyAuthentication=no option instructs the client not to attempt key pair authentication.

In addition, the PasswordAuthentication=yes option is to override any previously configured ssh options that may have disabled it.

Brian Minton
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Bill Weiss
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    And in fact 'ssh -o PreferredAuthentications=keyboard-interactive host' also works.

    I was thrown off by SSH_CONFIG(5), which still mentions the 'password' keyword.

    Thanks for the clarification.

     – Stefan Lasiewski Apr 07 '10 at 23:35
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    Correction: In SSH v2, both password and keyboard-interactive are valid, and they are different things. (password requires a password, and keyboard-interactive can technically be anything.) – grawity Apr 08 '10 at 12:17
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    Bill could you update your answer according to grawity's comment?

    Look at the output of these commands:

    lucian@XXX:~$ ssh -o PreferredAuthentications=keyboard-interactive -o PubkeyAuthentication=no host.example.org
Permission denied (publickey,gssapi-with-mic,password).

lucian@XXX:~$ ssh -o PreferredAuthentications=password -o PubkeyAuthentication=no host.example.org
lucian@host.example.org's password:
     – Lucian Adrian Grijincu Mar 15 '12 at 21:43
  • What does your server configuration look like? I've never seen that difference. As well, that wouldn't answer the original question, they were trying password. – Bill Weiss Mar 17 '12 at 12:00
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    If you want to add this switch to ssh's config file (~/.ssh/config) it's PubkeyAuthentication no in that file. – slm Aug 24 '12 at 16:17
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    ssh -o PubkeyAuthentication=no host.example.org worked for me, when ssh from debian to other debian. fyi – Sverre Oct 27 '14 at 07:05
  • Bingo, this works brilliantly – Daniel Mar 30 '16 at 05:06
  • I googled many phrases before I finally found this under ssh don't send key. Wow, this is hard to find. – bgStack15 Aug 31 '16 at 15:00
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    Doesn't work for me. I still get Permission denied (publickey). Looks like it's refusing to do anything else on the server end. – reinierpost Jul 27 '18 at 12:34
  • This works with ssh-copy-id as well, thanks for the answer! – Craig London Oct 08 '18 at 16:05
  • This works for scp as well – Silidrone Dec 26 '20 at 11:55
  • Works for me. Another solution is the option -o IdentitiesOnly=yes. – Daviz Apr 14 '21 at 09:25
  • Note to self - if you get intermittent key exchange failure, it's nothing to do with the key. The VM is out of memory and needs rebooting! – Sridhar Sarnobat Sep 09 '21 at 21:56
0

3rd party platforms such as virtual private server or cloud providers include their own settings in the Linux images provided which override custom SSH changes.

To enable SSH password authentication these changes also need to be made:

in /etc/ssh/ssd_config edit:

#Include /etc/ssh/sdd_confid./*conf

in /etc/cloud/cloud.cfg edit:

disable_root: false
ssh_pwauth: true

in /etc/cloud/cloud.cfg.d/00_defaults edit:

ssh_pwauth: true
nu_nad
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