Curtinator fails to create /etc/sudoers.d/90-cloud-init-users file

[Rod Smith]

Normally, MAAS installs include a file called /etc/sudoers.d/90-cloud-init-users, with the following contents:

# Created by cloud-init v. 0.7.5 on Wed, 07 Jan 2015 21:14:11 +0000

# User rules for ubuntu
ubuntu ALL=(ALL) NOPASSWD:ALL

(Presumably the date in the first line varies.) This file should be owned by root with 0440 permissions. Installations from images created by curtinator lack this file. Given the date on the comment line, I assume it's created dynamically by MAAS and something about the Curtinator image is blocking this, similar to bug #1408457; or maybe this is a bug in MAAS with respect to custom images. In any event, it would be helpful for Curtinator to create this file. As a workaround, I'm looking into doing it from the preseed.txt file.

This file, when present, enables the default "ubuntu" user to access "sudo" without a password, which is a practical necessity unless you want to publicize the default password set in the preseed.

[Rod Smith (rodsmith)]

As a workaround, the following two lines, added to the "d-i preseed/late_command" string, just prior to the "umount /target/sys" command, fix this problem:

  echo "ubuntu ALL=(ALL) NOPASSWD:ALL" > /target/etc/sudoers.d/90-cloud-init-users; \
  chmod 0440 /target/etc/sudoers.d/90-cloud-init-users; \

[Daniel Manrique (roadmr)]

I understand you're creating this file in a preseed, but watch out, as the file says it's created by cloud-init, so while the workaround sounds valid, we could perhaps try to understand why cloud-init isn't creating it in the first place.

[Rod Smith (rodsmith)]

Oh, that's in preseed.txt....

[Rod Smith (rodsmith)]

I agree; that's why I called this a workaround rather than a bug fix. ;-)

[Rod Smith (rodsmith)]

An update: It turns out that this bug applies ONLY to 12.04 releases. (I'm presuming all point releases, but I haven't tested them all.) With 14.04 GA and 14.04.1, the /etc/sudoers.d/90-cloud-init-users file is created correctly.

I've also found that a standard MAAS 12.04 installation has two files with similar contents, 90-cloudimg-ubuntu and 90-cloud-init-users, and neither file has the comment noting its creation by cloud-init that's present in 90-cloud-init-users on a 14.04 installation. The first file is present in the 12.04 image file stored on the MAAS server, but the second one isn't, so presumably it's created during deployment -- but the lack of a comment about cloud-init makes me wonder if it might be created in some other way than the file in 14.04, or at least that there might be some version-checking going on that's causing Curtinator-created images to slip through.