command - Executes a command on a remote node¶
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. It will not be processed through the shell, so variables like
$HOME
and operations like"<"
,">"
,"|"
,";"
and"&"
will not work (use the shell module if you need these features). - For Windows targets, use the win_command module instead.
Parameters¶
Parameter | Choices/Defaults | Comments |
---|---|---|
argv
(added in 2.6) |
Allows the user to provide the command as a list vs. a string. Only the string or the list form can be provided, not both. One or the other must be provided.
|
|
chdir |
Change into this directory before running the command.
|
|
creates |
A filename or (since 2.0) glob pattern. If it already exists, this step won't be run.
|
|
free_form
required |
The command module takes a free form command to run. There is no parameter actually named 'free form'. See the examples!
|
|
removes |
A filename or (since 2.0) glob pattern. If it already exists, this step will be run.
|
|
stdin
(added in 2.4) |
Set the stdin of the command directly to the specified value.
|
|
warn
bool (added in 1.8) |
|
If command_warnings are on in ansible.cfg, do not warn about this particular line if set to
no . |
Notes¶
Note
- If you want to run a command through the shell (say you are using
<
,>
,|
, etc), you actually want the 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 thecommand
module when possible. creates
,removes
, andchdir
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
orremoves
. 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 shell module instead. - For Windows targets, use the win_command module instead.
Examples¶
- name: return motd to registered var
command: cat /etc/motd
register: mymotd
- name: Run the command if the specified file does not exist.
command: /usr/bin/make_database.sh arg1 arg2
args:
creates: /path/to/database
# 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 /path/to/database doesn't exist.
command: /usr/bin/make_database.sh arg1 arg2
args:
chdir: somedir/
creates: /path/to/database
- name: use argv to send the command as a list. Be sure to leave command empty
command:
args:
argv:
- echo
- testing
- 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 |
---|---|---|
cmd
list
|
always |
the cmd that was run on the remote machine
Sample:
['echo', 'hello']
|
delta
string
|
always |
cmd end time - cmd start time
Sample:
0.001529
|
end
string
|
always |
cmd end time
Sample:
2017-09-29 22:03:48.084657
|
start
string
|
always |
cmd start time
Sample:
2017-09-29 22:03:48.083128
|
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.
Maintenance¶
This module is flagged as core which means that it is maintained by the Ansible Core Team. See Module Maintenance & Support for more info.
For a list of other modules that are also maintained by the Ansible Core Team, see here.
Support¶
For more information about Red Hat’s support of this module, please refer to this Knowledge Base article
Author¶
- Ansible Core Team
- Michael DeHaan
Hint
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