execute a command by switching to root user in ansible

Question

I am working on Ansible playbook to execute some of my tasks. In one of my tasks, I need to switch to particular directory and then execute a command using sudo but I need to do all these things by switching to root user first otherwise it won't work. So in general this is what I do without ansible:

david@machineA:/tmp/parallel-20140422$ sudo su
root@machineA:/tmp/parallel-20140422# sudo ./configure && make && make install

After above steps, I see GNU parallel library is installed in my system correctly. But with the below steps using Ansible, I don't see my GNU library getting installed at all.

- name: install gnu parallel
  command: chdir=/tmp/parallel-20140422 sudo ./configure && make && make install

Now my question is how can I switch to root user and execute a particular command. I am running Ansible 1.5.4 and looks like I cannot upgrade. I even tried with below but still it doesn't work:

- name: install gnu parallel
  command: chdir=/tmp/parallel-20140422 sudo ./configure && make && make install
  sudo: true
  sudo_user: root

I am running my playbook using below command:

ansible-playbook -e 'host_key_checking=False' setup.yml -u david --ask-pass --sudo -U root --ask-sudo-pass

I'm not sure about 1.5.4 but in Ansible 2.x you should use `shell` module instead of `command` when you want to execute arbitrary shell expression. And why do use `sudo` under `root` account, you already have maximum privileges? — Konstantin Suvorov, Jun 01 '17 at 19:47
yeah true on using sudo if I am already switched to root. I can change that part to not use sudo anymore if I already have switch to root user. — john, Jun 01 '17 at 19:51
I know command module is working fine bcoz I verified for other tasks and they work fine.. Somehow the issue for this task is I need to switch to root user and then only execute that command. And that I am not sure how can I do that using ansible. — john, Jun 01 '17 at 20:53

score 4 · Answer 1 · answered Jun 07 '17 at 20:34

You need the become directive.

For example, to start a service as root:

- name: Ensure the httpd service is running
  service:
    name: httpd
    state: started
  become: true

you can also become another user, such as the apache user:

- name: Run a command as the apache user
  command: somecommand
  become: true
  become_user: apache

For your case, it will be:

- name: install gnu parallel
  command: chdir=/tmp/parallel-20140422 sudo ./configure && make && make install
  become: true

In ansible 1.5.4 there is no become I believe? right? and I cannot upgrade looks like — , Jun 07 '17 at 20:41

score 1 · Answer 2 · answered Jun 08 '17 at 00:48

From your comment:

I know command module is working fine bcoz I verified for other tasks and they work fine.

command module might be working for other commands, but in this example you use a shell syntax (&&) to execute multiple commands. This syntax will not work in the command module (because this module runs commands directly from Python and does not support combined commands).

You need to use the shell module in this case.

- name: install gnu parallel 
  shell: ./configure && make && make install
  args:
    chdir=/tmp/parallel-20140422
  sudo: true
  sudo_user: root

execute a command by switching to root user in ansible

2 Answers2