ansible.builtin.command - Execute commands on targets
This module is part of ansible-base and included in all Ansible installations. In most cases, you can use the short module name command even without specifying the collections: keyword. Despite that, we recommend you use the FQCN for easy linking to the module documentation and to avoid conflicting with other collections that may have the same module name.
Synopsis
- The command module takes the command name followed by a list of space-delimited arguments.
- The given command will be executed on all selected nodes.
- The command(s) will not be processed through the shell, so variables like $HOSTNAME and operations like "*", "<", ">", "|", ";" and "&" will not work. Use the ansible.builtin.shell module if you need these features.
- To create command tasks that are easier to read than the ones using space-delimited arguments, pass parameters using the args task keyword or use cmd parameter.
- Either a free form command or cmd parameter is required, see the examples.
- For Windows targets, use the ansible.windows.win_command module instead.
This module has a corresponding action plugin.
Parameters
Parameter Choices/Defaults Comments list / elements=string
Passes the command as a list rather than a string.
Use argv to avoid quoting values that would otherwise be interpreted incorrectly (for example "user name").
Only the string (free form) or the list (argv) form can be provided, not both. One or the other must be provided.
path
Change into this directory before running the command.
string
The command to run.
path
A filename or (since 2.0) glob pattern. If a matching file already exists, this step won't be run.
string
The command module takes a free form string as a command to run.
There is no actual parameter named 'free form'.
path
A filename or (since 2.0) glob pattern. If a matching file exists, this step will be run.
string
Set the stdin of the command directly to the specified value.
boolean
- no
- yes ←
If set to yes, append a newline to stdin data.
boolean
- no
- yes ←
Strip empty lines from the end of stdout/stderr in result.
boolean
- no
- yes ←
Enable or disable task warnings.
Notes
- If you want to run a command through the shell (say you are using <, >, |, etc), you actually want the ansible.builtin.shell module instead. Parsing shell metacharacters can lead to unexpected commands being executed if quoting is not done correctly so it is more secure to use the command module when possible.
- creates, removes, and chdir can be specified after the command. For instance, if you only want to run a command if a certain file does not exist, use this.
- Check mode is supported when passing creates or removes. If running in check mode and either of these are specified, the module will check for the existence of the file and report the correct changed status. If these are not supplied, the task will be skipped.
- The executable parameter is removed since version 2.4. If you have a need for this parameter, use the ansible.builtin.shell module instead.
- For Windows targets, use the ansible.windows.win_command module instead.
- For rebooting systems, use the ansible.builtin.reboot or ansible.windows.win_reboot module.
See Also
See also
- ansible.builtin.raw
The official documentation on the ansible.builtin.raw module.
- ansible.builtin.script
The official documentation on the ansible.builtin.script module.
- ansible.builtin.shell
The official documentation on the ansible.builtin.shell module.
- ansible.windows.win_command
The official documentation on the ansible.windows.win_command module.
Examples
- name: Return motd to registered var command: cat /etc/motd register: mymotd # free-form (string) arguments, all arguments on one line - name: Run command if /path/to/database does not exist (without 'args') command: /usr/bin/make_database.sh db_user db_name creates=/path/to/database # free-form (string) arguments, some arguments on separate lines with the 'args' keyword # 'args' is a task keyword, passed at the same level as the module - name: Run command if /path/to/database does not exist (with 'args' keyword) command: /usr/bin/make_database.sh db_user db_name args: creates: /path/to/database # 'cmd' is module parameter - name: Run command if /path/to/database does not exist (with 'cmd' parameter) command: cmd: /usr/bin/make_database.sh db_user db_name creates: /path/to/database - name: Change the working directory to somedir/ and run the command as db_owner if /path/to/database does not exist command: /usr/bin/make_database.sh db_user db_name become: yes become_user: db_owner args: chdir: somedir/ creates: /path/to/database # argv (list) arguments, each argument on a separate line, 'args' keyword not necessary # 'argv' is a parameter, indented one level from the module - name: Use 'argv' to send a command as a list - leave 'command' empty command: argv: - /usr/bin/make_database.sh - Username with whitespace - dbname with whitespace creates: /path/to/database - name: Safely use templated variable to run command. Always use the quote filter to avoid injection issues command: cat {{ myfile|quote }} register: myoutput
Return Values
Common return values are documented here, the following are the fields unique to this module:
Key Returned Description list / elements=string
always The command executed by the task
Sample:
['echo', 'hello']
string
always The command execution delta time
Sample:
0:00:00.001529
string
always The command execution end time
Sample:
2017-09-29 22:03:48.084657
boolean
always changed
Sample:
True
integer
always The command return code (0 means success)
string
always The command execution start time
Sample:
2017-09-29 22:03:48.083128
string
always The command standard error
Sample:
ls cannot access foo: No such file or directory
list / elements=string
always The command standard error split in lines
Sample:
[{"u'ls cannot access foo": "No such file or directory'"}, "u'ls …'"]
string
always The command standard output
Sample:
Clustering node [email protected] with [email protected] …
list / elements=string
always The command standard output split in lines
Sample:
["u'Clustering node [email protected] with [email protected] …'"]
Authors
- Ansible Core Team
- Michael DeHaan