passwordless sudo using ubuntu preseed and packer

Question

I am attempting to grant passwordless sudo privileges to a user created during Ubuntu 14.04 install. However when the image is created none of the changes related to sudo exist. Here are the relevant parts of the preseed file:

# Create Vagrant User
d-i passwd/user-fullname string Vagrant User
d-i passwd/username string vagrant
d-i passwd/user-password password vagrant
d-i passwd/user-password-again password vagrant
d-i user-setup/encrypt-home boolean false
d-i user-setup/allow-password-weak boolean true

# Setup passwordless sudo for vagrant user
d-i preseed/late_command string echo "vagrant   ALL=(ALL:ALL) NOPASSWD:ALL" > /target/etc/sudoers.d/vagrant
d-i preseed/late_command string chmod 0440 /target/etc/sudoers.d/vagrant

I have also tried

d-i preseed/late_command string in-target echo "vagrant ALL=(ALL:ALL) NOPASSWD:ALL" > /etc/sudoers.d/vagrant

When the image finishes /etc/sudoers.d/vagrant will not exist anywhere.

even if I run the commands:

d-i preseed/late_command string mkdir /stuff
d-i preseed/late_command string in-target mkdir /stuff

the stuff directory will not exist.

I know the commands are being run because I made a typo once and saw an error during install. All other preseed commands seem to be working.

I have read about the in-target directive and that the installer will create a /target that has the finial filesystem however I seem unable to make these work.

using packer I have run a shell script provisioned that does the same echo and that works.

Answer 1

The problem is that a preseed file can only have one preseed/late_command section, not multiple.

If you need to execute multiple commands, you can have them as a single late_command separated with ; e.g.

d-i preseed/late_command string \
    in-target cmd1 args ... ; \
    in-target cmd2 args ... ; \
    ...

Answer 2

In this particular case, this is what was working for me:

d-i preseed/late_command string \
    echo 'vagrant ALL=(ALL) NOPASSWD: ALL' > /target/etc/sudoers.d/vagrant ; \
    in-target chmod 440 /etc/sudoers.d/vagrant ;