--- name: "clush.conf" section: "5" platform: "linux" package: "clustershell" version: "1.10.1-2" release: "Arch Linux 2026-11-01" platforms: ["linux"] url: "https://new.carta.tech/clush.conf" --- # clush.conf(5) Configuration file for clush ## NAME clush.conf - Configuration file for clush ## DESCRIPTION [**clush**(1)](/clush/1.md) configuration files are in Python's ConfigParser format. ### Locations [**clush**(1)](/clush/1.md) obtains configuration options from the following sources, in decreasing order of precedence: - 1\. command-line options - 2\. *$CLUSTERSHELL\_CFGDIR/clush.conf* (only used when $CLUSTERSHELL\_CFGDIR is defined) - 3\. user configuration file (*$XDG\_CONFIG\_HOME/clustershell/clush.conf*, defaults to *$HOME/.config/clustershell/clush.conf*) - 4\. Python virtual environment (*{sys.prefix}/etc/clustershell/clush.conf*) - 5\. local pip user installation (*$HOME/.local/etc/clustershell/clush.conf*) - 6\. system-wide configuration file (*/etc/clustershell/clush.conf*) For each parameter, the first obtained value will be used. The configuration file has a format in the style of RFC 822 composed of one main section: - **Main** Program options definition ### \[Main\] Configuration parameters of the **Main** section are described below. - **fanout** Size of the sliding window (fanout) of active commands for **clush**. This *fanout* is used to avoid too many concurrent connections and to conserve resources on the initiating hosts. In tree mode, the same *fanout* value is used on the head node and on each gateway (the *fanout* value is propagated). That is, if the *fanout* is **16** on the head node, each gateway will initiate up to **16** connections to their target nodes at the same time. - **confdir** Optional list of directory paths where clush should look for *.conf* files which define run modes that can then be activated with **--mode**. All other clush config file settings defined here might be overridden in a run mode. Each mode section should have a name prefixed by "mode:" to clearly identify a section defining a mode. Duplicate modes are not allowed in those files. Configuration files that are not readable by the current user are ignored. The variable *$CFGDIR* is replaced by the path of the highest priority configuration directory found (where clush.conf resides). The default confdir value enables both system-wide and any installed user configuration (thanks to *$CFGDIR*). Duplicate directory paths are ignored. - **connect\_timeout** Timeout in seconds to allow a connection to establish. This parameter is passed to ssh. If set to *0*, no timeout occurs. - **command\_prefix** Command prefix. Generally used for specific run modes, for example to implement [**sudo**(8)](/sudo/8.md) support. - **command\_timeout** Timeout in seconds to allow a command to complete since the connection has been established. This parameter is passed to ssh. In addition, the ClusterShell library ensures that any commands complete in less than ( connect\_timeout + command\_timeout ). If set to *0*, no timeout occurs. - **color** **clush** can use NO\_COLOR, CLICOLOR and CLICOLOR\_FORCE environment variables. NO\_COLOR takes precedence over CLICOLOR\_FORCE which takes precedence over CLICOLOR. When the option is set in configuration file environment variables are taken into account only with *auto* argument. **color** tells whether to use ANSI colors to surround node or nodeset prefix/header with escape sequences to display them in color on the terminal. Valid arguments are **never**, **always** or **auto** (which uses color if standard output/error refer to a terminal). Colors are set to \[34m (blue foreground text) for stdout and \[31m (red foreground text) for stderr, and cannot be modified. - **fd\_max** Maximum number of open file descriptors permitted per clush process (soft resource limit for open files). This limit can never exceed the system (hard) limit. The *fd\_max* (soft) and system (hard) limits should be high enough to run **clush**, although their values depend on your *fanout* value. - **history\_size** Set the maximum number of history entries saved in the GNU readline history list. Negative values imply unlimited history file size. - **node\_count** Should **clush** display additional (node count) information in buffer header? (*yes*/*no*) - **maxrc** Should **clush** return the largest of command return codes? (yes/no) - **password\_prompt** Enable password prompt and password forwarding to stdin? (yes/no) Generally used for specific run modes, for example to implement interactive [**sudo**(8)](/sudo/8.md) support. - **verbosity** Set the verbosity level: *0* (quiet), *1* (default), *2* (verbose) or more (debug). - **ssh\_user** Set the ssh user to use for remote connection (default is to not specify). - **ssh\_path** Set the ssh binary path to use for remote connection (default is *ssh*). - **ssh\_options** Set additional options to pass to the underlying ssh command. - **scp\_path** Set the scp binary path to use for remote copy (default is *scp*). - **scp\_options** Set additional options to pass to the underlying scp command. If not specified, ssh\_options are used instead. - **rsh\_path** Set the rsh binary path to use for remote connection (default is *rsh*). You could easily use mrsh or krsh by simply changing this value. - **rcp\_path** Same as rsh\_path for rcp command. (Default is *rcp*) - **rsh\_options** Set additional options to pass to the underlying rsh/rcp command. ### Run modes Since version 1.9, clush has support for run modes, which are special [**clush.conf**(5)](/clush.conf/5.md) settings with a given name. Two run modes are provided in example configuration files that can be copied and modified. They implement password-based authentication with [**sshpass**(1)](/sshpass/1.md) and support of interactive [**sudo**(8)](/sudo/8.md) with password. To use a run mode with **clush --mode**, install a configuration file in one of [**clush.conf**(5)](/clush.conf/5.md)'s *confdir* (usually **clush.conf.d**). Only configuration files ending in *.conf* are scanned. If the user running [**clush**(1)](/clush/1.md) doesn't have read access to a configuration file, it is ignored. When **--mode** is specified, you can display all available run modes for the current user by enabling debug mode (**-d**). ## EXAMPLES Simple configuration file. ### *clush.conf* ``` [Main] fanout: 128 connect_timeout: 15 command_timeout: 0 history_size: 100 color: auto fd_max: 10240 maxrc: no node_count: yes confdir: /etc/clustershell/clush.conf.d ``` ## FILES - ***$CLUSTERSHELL\_CFGDIR/clush.conf*** Global clush configuration file. If $CLUSTERSHELL\_CFGDIR is not defined, */etc/clustershell/clush.conf* is used instead. - ***$XDG\_CONFIG\_HOME/clustershell/clush.conf*** User configuration file for clush. If $XDG\_CONFIG\_HOME is not defined, *$HOME/.config/clustershell/clush.conf* is used instead. - ***{sys.prefix}/etc/clustershell/clush.conf*** Configuration file when ClusterShell is installed in a Python virtual environment. - ***$HOME/.local/etc/clustershell/clush.conf*** Local user configuration file for clush (default installation for pip --user) - ***~/.clush.conf*** Deprecated per-user clush configuration file (no longer read since version 1.9). ## HISTORY As of ClusterShell version 1.3, the **External** section has been removed from *clush.conf*. External commands whose outputs were used by **clush** (-a, -g, -X) are now handled by the library itself and defined in [**groups.conf**(5)](/groups.conf/5.md). ## SEE ALSO [**clush**(1)](/clush/1.md), [**groups.conf**(5)](/groups.conf/5.md), [**sshpass**(1)](/sshpass/1.md), [**sudo**(8)](/sudo/8.md). *https://clustershell.readthedocs.io/* Python ConfigParser *https://docs.python.org/3/library/configparser.html* ## AUTHOR Stephane Thiell ## COPYRIGHT GNU Lesser General Public License version 2.1 or later (LGPLv2.1+)