ansible/docsite/rst/become.rst

Become (Privilege Escalation)
+++++++++++++++++++++++++++++

Ansible can use existing privilege escalation systems to allow a user to execute tasks as another.

.. contents:: Topics

Become
``````
Ansible allows you 'become' another user, different from the user that logged into the machine (remote user). This is done existing
privilege escalation tools, which you probably already use or have configured, like 'sudo', 'su', 'pfexec', 'doas', 'pbrun' and others.


.. note:: Before 1.9 Ansible mostly allowed the use of `sudo` and a limited use of `su` to allow a login/remote user to become a different user
    and execute tasks, create resources with the 2nd user's permissions. As of 1.9 `become` supersedes the old sudo/su, while still being backwards compatible.
    This new system also makes it easier to add other privilege escalation tools like `pbrun` (Powerbroker), `pfexec` and others.

.. note:: Setting any var or directive makes no implications on the values of the other related directives, i.e. setting become_user does not set become.


Directives
-----------
These can be set from play to task level, but are overriden by connection variables as they can be host specific.

become
    set to 'true'/'yes' to activate privilege escalation.

become_user
    set to user with desired privileges, the user you 'become', NOT the user you login as. Does NOT imply `become: yes`, to allow it to be set at host level.

become_method
    at play or task level overrides the default method set in ansible.cfg, set to 'sudo'/'su'/'pbrun'/'pfexec'/'doas'


Connection variables
--------------------
Each allows you to set an option per group and/or host, these are normally defined in inventory but can be used as normal variables.

ansible_become
    equivalent of the become directive, decides if privilege escalation is used or not.

ansible_become_method
    allows to set privilege escalation method

ansible_become_user
    allows to set the user you become through privilege escalation, does not imply `ansible_become: True`

ansible_become_pass
    allows you to set the privilege escalation password


New command line options
------------------------

--ask-become-pass, -K
    ask for privilege escalation password, does not imply become will be used

--become, -b
    run operations with become (no password implied)

--become-method=BECOME_METHOD
    privilege escalation method to use (default=sudo),
    valid choices: [ sudo | su | pbrun | pfexec | doas ]

--become-user=BECOME_USER
    run operations as this user (default=root), does not imply --become/-b


For those from Pre 1.9 , sudo and su still work!
------------------------------------------------

For those using old playbooks will not need to be changed, even though they are deprecated, sudo and su directives, variables and options
will continue to work. It is recommended to move to become as they may be retired at one point.
You cannot mix directives on the same object (become and sudo) though, Ansible will complain if you try to.

Become will default to using the old sudo/su configs and variables if they exist, but will override them if you specify any of the new ones.


.. note:: Privilege escalation methods must also be supported by the connection plugin used, most will warn if they do not, some will just ignore it as they always run as root (jail, chroot, etc).

.. note:: Methods cannot be chained, you cannot use 'sudo /bin/su -' to become a user, you need to have privileges to run the command as that user in sudo or be able to su directly to it (the same for pbrun, pfexec or other supported methods).

.. note:: Privilege escalation permissions have to be general, Ansible does not always use a specific command to do something but runs modules (code) from a temporary file name which changes every time. So if you have '/sbin/service' or '/bin/chmod' as the allowed commands this will fail with ansible.

.. seealso::

   `Mailing List <http://groups.google.com/group/ansible-project>`_
       Questions? Help? Ideas?  Stop by the list on Google Groups
   `irc.freenode.net <http://irc.freenode.net>`_
       #ansible IRC chat channel