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