dsh
From Gentoo Wiki
dsh is a shell that allows parallel execution of remote commands across large numbers of servers. Generally called "distributed shell" dsh was often leveraged as an orchestration tool prior to the rise of modern alternatives. Even to this day, dsh is still used by some system administrators where heavyweight tools such as Ansible are impractical or inefficient.
Installation
USE flags
USE flags for app-shells/dsh Distributed Shell
nls
|
Add Native Language Support (using gettext - GNU locale utilities) |
Emerge
root #
emerge --ask app-shells/dsh
Configuration
Environment variables
- $DSH_FANOUT - the maximum number of concurrent remote shell commands
- $DSH_REMOTE_CMD - used to specify a remote shell other than the default rsh, typically ssh.
- $DSH_NODE_LIST - the location of the host list.
- $WCOLL - (deprecated) the location of the host list.
- $DSH_PATH - the default path for remote command execution, $PATH by default.
Files
Global Configuration Files
- /etc/dsh/machines.list - the list of machine names to be used for when -a command-line option is specified.
- /etc/dsh/group/<group_name> - the list of machine names to be used for when -g group name command-line option is specified.
- /etc/dsh/dsh.conf - the configuration file containing the day-to-day default.
User Specific Configuration Files
- $HOME/.dsh/machines.list - the list of machine names to be used for when -a command-line option is specified.
- $HOME/.dsh/group/<group_name> - the list of machine names to be used for when -g group name command-line option is specified.
- $HOME/.dsh/dsh.conf - the configuration file containing the day-to-day default.
Usage
First, tell dsh where to find the server list:
user $
DSH_NODE_LIST=~/<server.list>
Second, tell dsh what command to run:
user $
dsh -v '<remote_command>'
Note
Without the -v (verbose) flag remote commands will be executed but no output will be visible to the user.
Without the -v (verbose) flag remote commands will be executed but no output will be visible to the user.
Invocation
user $
dsh --help
Distributed Shell / Dancer's shell version 0.25.10 Copyright 2001-2005 Junichi Uekawa, distributed under the terms and conditions of GPL version 2 -v --verbose Verbose output -q --quiet Quiet -M --show-machine-names Prepend the host name on output -H --hide-machine-names Do not prepend host name on output -i --duplicate-input Duplicate input given to dsh -b --bufsize Change buffer size used in input duplication -m --machine [machinename] Execute on machine -n --num-topology How to divide the machines -a --all Execute on all machines -g --group [groupname] Execute on group member -f --file [file] Use the file as list of machines -r --remoteshell [shellname] Execute using shell (rsh/ssh) -o --remoteshellopt [option] Option to give to shell -h --help Give out this message -w --wait-shell Sequentially execute shell -c --concurrent-shell Execute shell concurrently -F --forklimit [fork limit] Concurrent with limit on number -V --version Give out version information