24.3. The Command Shell Module

One problem with the SSH/Telnet Login module is its inability to connect if there is a firewall of some kind blocking telnet or SSH connections to your system. Even though the rest of Webmin may work fine using HTTP connections, the ports used by the applet may not be available. Even though it is possible to do almost everything in Webmin that you can do at the command line, it is sometimes useful to have a shell prompt for executing UNIX commands.

To get around firewall restrictions that prevent an SSH or telnet connection, you can use the Command Shell module, found under the Others category. It allows you to enter shell commands into the field next to the Execute command button that are run when the button is clicked or the return key pressed. All output from the command is displayed in the Command history section at the top of the page.

You can rerun old commands by selecting them from the menu next to the Execute previous command button, and then clicking it. If the command history becomes too large, it can be wiped clean using the Clear history button. This will not affect the menu of previously run commands.

The module's biggest limitation is that interactive commands like vi, passwd, and telnet cannot be run. There is no support for providing input to a command once it has started, so you are limited to noninteractive programs like cp, ls, and rm.