create a new ssh unser with webmin

October 21, 2015 429 views

hi .. i want to ask about linux . perhaps no one knows the function of the following Linux command ? at the time wanted to make unser ssh with webmin , the shell column contained the following command

  1. / bin / sh
  2. / bin / csh
  3. / bin / false
  4. / bin / bash
  5. / usr / sbin / nologin
  6. / bin / sync
  7. / bin / dash
  8. / bin / rbash

what the function of each command it ? please help

1 comment
  • Those are available shell options; they are not specific to Webmin. They come from the /etc/shells file, and apply to any user created by any means (whether using useradd, adduser, Webmin, or manually created).

    sh, csh, bash, dash, and rbash are all regular shells, with varying capabilities. rbash is a restricted bash, often used in conjunction with chroot.

    false and nologin are different types of shell that prevent logins. nologin is more "polite" and can be configured to display a message explaining that logins are disallowed.

    sync is for syncing changed blocks to disk (to prepare for system shutdown). I have no idea why it would be listed in /etc/shells. It is not a user shell, and you'd probably never have a reason to choose it for a user.

    Most people should use bash most of the time, unless you have some reason to choose something else. bash is the most common default shell on Linux, and is a powerful, modern, shell.

1 Answer

These are different possible shells (the shell provides the command line interface that you use when you are logged in). Some of these may not be installed on your system and others, like /usr/sbin/nologin are there to prevent a login at all. Generally you would want to select /bin/sh or /bin/bash which are installed by default in all OS options and will provide a familiar Linux CLI experience.

Have another answer? Share your knowledge.