shell – Execute shell commands on targets
Synopsis
- The
shell
module takes the command name followed by a list of space-delimited arguments. - Either a free form command or
cmd
parameter is required, see the examples. - It is almost exactly like the command module but runs the command through a shell (
/bin/sh
) on the remote node. - For Windows targets, use the win_shell module instead.
Parameters
Parameter | Choices/Defaults | Comments |
---|---|---|
chdir path | Change into this directory before running the command. | |
cmd string | The command to run followed by optional arguments. | |
creates path | A filename, when it already exists, this step will not be run. | |
executable path | Change the shell used to execute the command. This expects an absolute path to the executable. | |
free_form string | The shell module takes a free form command to run, as a string. There is no actual parameter named 'free form'. See the examples on how to use this module. | |
removes path | A filename, when it does not exist, this step will not be run. | |
stdin string added in 2.4 | Set the stdin of the command directly to the specified value. | |
stdin_add_newline boolean added in 2.8 |
| Whether to append a newline to stdin data. |
warn boolean |
| Whether to enable task warnings. |
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. - 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. - To sanitize any variables passed to the shell module, you should use
{{ var | quote }}
instead of just{{ var }}
to make sure they do not include evil things like semicolons. - An alternative to using inline shell scripts with this module is to use the script module possibly together with the template module.
- For rebooting systems, use the reboot or win_reboot module.
See Also
See also
- command – Execute commands on targets
- The official documentation on the command module.
- raw – Executes a low-down and dirty command
- The official documentation on the raw module.
- script – Runs a local script on a remote node after transferring it
- The official documentation on the script module.
- win_shell – Execute shell commands on target hosts
- The official documentation on the win_shell module.
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 # You can also use the 'cmd' parameter instead of free form format. - name: This command will change the working directory to somedir/. shell: cmd: ls -l | grep log chdir: somedir/ - 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 # Disabling warnings - name: Using curl to connect to a host via SOCKS proxy (unsupported in uri). Ordinarily this would throw a warning. shell: curl --socks5 localhost:9000 http://www.ansible.com args: warn: no
Return Values
Common return values are documented here, the following are the fields unique to this module:
Key | Returned | Description |
---|---|---|
cmd string | always | The command executed by the task Sample: rabbitmqctl join_cluster rabbit@master |
delta string | always | The command execution delta time Sample: 0:00:00.325771 |
end string | always | The command execution end time Sample: 2016-02-25 09:18:26.755339 |
msg boolean | always | changed Sample: True |
rc integer | always | The command return code (0 means success) |
start string | always | The command execution start time Sample: 2016-02-25 09:18:26.429568 |
stderr string | always | The command standard error Sample: ls: cannot access foo: No such file or directory |
stdout string | always | The command standard output Sample: Clustering node rabbit@slave1 with rabbit@master ... |
stdout_lines list | always | The command standard output split in lines Sample: ["u'Clustering node rabbit@slave1 with rabbit@master ...'"] |
Status
- This module is guaranteed to have backward compatible interface changes going forward. [stableinterface]
- This module is maintained by the Ansible Core Team. [core]
Red Hat Support
More information about Red Hat’s support of this module is available from this Red Hat Knowledge Base article.
Authors
- Ansible Core Team
- Michael DeHaan
Hint
If you notice any issues in this documentation, you can edit this document to improve it.
© 2012–2018 Michael DeHaan
© 2018–2019 Red Hat, Inc.
Licensed under the GNU General Public License version 3.
https://docs.ansible.com/ansible/2.9/modules/shell_module.html