CODEWITHSUNDEEP
ubuntuamazon-web-servicesamazon-ec2amazon-ami
Dan Tenenbaum
Dan Tenenbaum

Reputation: 1889

changed password for ubuntu user does not survive making a new AMI from instance

I am working on an Ubuntu AMI on Amazon EC2.

On a running instance, I changed the password of the ubuntu user to (let's say) 'foobar'.

(I know user passwords are not generally needed in EC2 because of ssh with public/private keys, but I'm setting up a web application that authenticates using unix usernames/passwords, so I need to make sure this works.)

I tried several ways of setting the password:

  1. sudo passwd ubuntu
  2. echo "ubuntu:foobar" | chpasswd
  3. Setting it with chef's 'user' resource

In all cases, if I then make a new image from the running instance, and then create an instance of that image, the ubuntu user will NOT have the password 'foobar'.

I can set the password and reboot a running instance and the correct password will still be set, but after making a new image from the instance, no such luck.

This has worked for me before. Not sure why it's not working now. It's an EBS image.

EDIT: Adding the exact steps to reproduce the problem.

Upvotes: 2

Views: 3602

Answers (3)

developerCK
developerCK

Reputation: 4506

Its' too late to answer, Still , Just for reference,

When launching an instance from an image, AWS will disbale the root and main account for password authentication.

  • in case ubuntu [user : root,ubuntu]
  • in case ami : [user : ec2-user]

It means , these account can not login through password authentication on a fresh launched ec2.

However, any other account, will be working. so let's suppose, you create an instance from ubuntu, set password authentication yes in ssh and setup password for ubuntu, along with this, you created another user for your self, then ,you launch one instance from the image of above configured ec2.

then password authentication for ubuntu user will not work , hwoever, password authentication for another user will work.

Upvotes: 2

Dan Tenenbaum
Dan Tenenbaum

Reputation: 1889

The answer, according to Hugh MacMullan on the Starcluster list, is:

"Have a look at /etc/cloud/cloud.cfg, particularly the 'default_user' section. Notice the 'lock_passwd: True'. You could change that to False ... OR better would be to create a different user (say, rlogin), which will NOT be locked by default on init, so you should be good to go."

I changed lock_passwd to False and my password change survived a reboot. No need for insecure crontab hacks.

Upvotes: 0

Nikhil
Nikhil

Reputation: 3152

Not to sound belittling, but this has happened to me before when I realized my AMI was created before I made the change to the password.

If that's not it, you might want to modify the sshd_config file as well. After changing the password with 'sudo passwd ubuntu', add the following line to your /etc/ssh/sshd_config:

PasswordAuthentication yes

This should enable password login. Reload your ssh with:

sudo reload ssh

and subsequently create a new AMI.

Upvotes: 0

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