Super User is a question and answer site for computer enthusiasts and power users. It's 100% free, no registration required.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I am using Debian 6.0 and I am trying to auto login into Debian 4.0. I generated rsa keys with ssh-keygen on Debian 6.0 and I copied id_rsa on Debian 4.0 in /root/.ssh/authorized_keys. When I tried to ssh from Debian 6.0, ssh is giving the following error and asking for password. Can anyone help me, how can I solve the problem to perform autologin?

Error: Agent admitted failure to sign using the key.

share|improve this question

migrated from May 21 '11 at 21:34

This question came from our site for professional and enthusiast programmers.

Did you Google this error message? I haven't seen it before. – Robin Green May 20 '11 at 13:03
This is a horrible idea to give root ssh access with a passwordless key. You need to be creating a user for the specific task at hand. If you need to have a passwordless key look into this article. – grantk May 20 '11 at 13:03
Definitely agree with you grantk. IF you are going to provide root access via a key, it NEEDS to have a password - otherwise you may aswell be storing the root password in a text file and using plain authentication. Infact, any key-based auth should have a password, in my opinion. – Seidr May 20 '11 at 13:06
@Seidr - I agree to a point. How do you handle a situation where a automated script has to connect to another host? – grantk May 20 '11 at 13:07
@grantk - in that situation your suggestion for a separate user (locked down to all but the required directories/utilities) would be the best solution, otherwise again you're providing the ability to authenticate in the CRON/Scheduled Task :) – Seidr May 20 '11 at 13:11

Check the permissions - the .ssh dir needs to CHMOD to 600, and the authorized_keys file to 644 (or also 600, I can't recall). Unsure if this is what is causing your problem - but it's an idea.

share|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.