Systemd exact commands for sudoers file

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1

Hello everyone,

I’m currently trying to update a couple of configuration scripts of a server.
The steps I want to do:

  1. Stop service
  2. Copy new configuration files for this service
  3. Start service

I have a sudoers file that allows the remote user to run systemctl start/stop/show/status for this specific service.
The sudoers file:

%REDACTED ALL= NOPASSWD: /bin/systemctl start REDACTED
%REDACTED ALL= NOPASSWD: /bin/systemctl stop REDACTED
%REDACTED ALL= NOPASSWD: /bin/systemctl restart REDACTED
%REDACTED ALL= NOPASSWD: /bin/systemctl status REDACTED
%REDACTED ALL= NOPASSWD: /bin/systemctl show

The problem is now that the commands in the sudoers file most likely not fit the commands ansible is using.
The task I want to run is:

    - name: "Stop service {{ service_name }}"
      ansible.builtin.systemd_service:
        name: "{{ service_name }}"
        state: stopped
      become: true

It fails with “password required”. The question is now, is there a way to edit the sudoers file to have ansible working without giving NOPASSWD Permissions on every command for the remote user?
Using ansible.builtin.command it works

2

You may also need:

%REDACTED ALL= NOPASSWD: /bin/systemctl show 'REDACTED'
%REDACTED ALL= NOPASSWD: /bin/systemctl list-unit-files *
%REDACTED ALL= NOPASSWD: /bin/systemctl is-active 'REDACTED'

since the module first checks to see if the specified unit exists before attempting to make any required changes. Note also the ' characters, as sudo rules without any wildcards must be exact matches, and the module is single quoting the given unit name. I did use a wildcard for list-unit-files, but that’s because I’m not sure how to easily interpret the following '{unit_search}*', since it’s a manipulation of the original unit name. The single-quotes around the unit name are also used by the module for all of the start/stop/restart/reload actions.

Additionally, I’m not familiar enough with sudo rules to know if it cares about symlink paths. Usually, /bin and /usr/bin are symlinked, and Ansible isn’t using an explicit path to systemctl, so Ansible might be trying to use /usr/bin/systemctl while all of your rules are for /bin/systemctl. This might be an important distinction for the sudo rules.

Edit: for reference: ansible/lib/ansible/modules/systemd_service.py at devel · ansible/ansible (github.com)

3

Unfortunately it seems to just not work. The become does not prepend the sudo to each command but to the whole python command which is used for the subcommand e.g.:

sudo -H -S -n  -u root /bin/sh -c '"'"'"'"'"'"'"'"'echo BECOME-SUCCESS-htbihlgskndrxzpaectqhiopugwdsxww ; /usr/bin/python3 /home/USER/.ansible/tmp/ansible-tmp-1725957415.6666732-2937536-137956451165161/AnsiballZ_systemd_service.py'"'"'"'"'"'"'"'"' && sleep 0
4

Assuming modules will just use a specific command is not really possible, hence why:

https://docs.ansible.com/ansible/latest/playbook_guide/playbooks_privilege_escalation.html#privilege-escalation-must-be-general

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