Documentation

shell - Execute commands in nodes.

Synopsis

  • The shell module takes the command name followed by a list of space-delimited arguments. It is almost exactly like the command module but runs the command through a shell (/bin/sh) on the remote node.

Options

parameter required default choices comments
chdir
no
cd into this directory before running the command
creates
no
a filename, when it already exists, this step will not be run.
executable
no
change the shell used to execute the command. Should be an absolute path to the executable.
free_form
yes
The shell module takes a free form command to run, as a string. There's not an actual option named "free form". See the examples!
removes
no
a filename, when it does not exist, this step will not be run.
warn
(added in 1.8)
no True
if command warnings are on in ansible.cfg, do not warn about this particular line if set to no/false.

Examples

- name: Execute the command in remote shell; stdout goes to the specified file on the remote.
  shell: somescript.sh >> somelog.txt

- name: Change the working directory to somedir/ before executing the command.
  shell: somescript.sh >> somelog.txt
  args:
    chdir: somedir/

# You can also use the 'args' form to provide the options.
- name: This command will change the working directory to somedir/ and will only run when somedir/somelog.txt doesn't exist.
  shell: somescript.sh >> somelog.txt
  args:
    chdir: somedir/
    creates: somelog.txt

- name: Run a command that uses non-posix shell-isms (in this example /bin/sh doesn't handle redirection and wildcards together but bash does)
  shell: cat < /tmp/*txt
  args:
    executable: /bin/bash

- name: Run a command using a templated variable (always use quote filter to avoid injection)
  shell: cat {{ myfile|quote }}

# You can use shell to run other executables to perform actions inline
- name: Run expect to wait for a successful PXE boot via out-of-band CIMC
  shell: |
    set timeout 300
    spawn ssh admin@{{ cimc_host }}

    expect "password:"
    send "{{ cimc_password }}\n"

    expect "\n{{ cimc_name }}"
    send "connect host\n"

    expect "pxeboot.n12"
    send "\n"

    exit 0
  args:
    executable: /usr/bin/expect
  delegate_to: localhost

Return Values

Common return values are documented here Return Values, the following are the fields unique to this module:

name description returned type sample
end The command execution end time always string 2016-02-25 09:18:26.755339
stdout The command standard output always string Clustering node [email protected] with [email protected] ...
cmd The command executed by the task always string rabbitmqctl join_cluster [email protected]
start The command execution start time always string 2016-02-25 09:18:26.429568
delta The command execution delta time always string 0:00:00.325771
stderr The command standard error always string ls: cannot access foo: No such file or directory
rc The command return code (0 means success) always int 0
msg changed always boolean True
stdout_lines The command standard output split in lines always list ["u'Clustering node [email protected] with [email protected] ...'"]


Notes

Note

  • If you want to execute a command securely and predictably, it may be better to use the command module instead. Best practices when writing playbooks will follow the trend of using command unless the shell module is explicitly required. When running ad-hoc commands, use your best judgement.
  • To sanitize any variables passed to the shell module, you should use “{{ var | quote }}” instead of just “{{ var }}” to make sure they don’t include evil things like semicolons.

Status

This module is flagged as stableinterface which means that the maintainers for this module guarantee that no backward incompatible interface changes will be made.

Support

This module is maintained by those with core commit privileges

For more information on what this means please read Module Support

For help in developing on modules, should you be so inclined, please read Community Information & Contributing, Testing Ansible and Developing Modules.