What if -m is not used?

If the -m option is not used with the useradd command, the new user account will be created without a home directory. This can lead to several issues:

1. No Personal Space: The user will not have a designated area to store personal files, configurations, or settings. This can hinder their ability to use the system effectively.

2. Default Configuration Issues: Many applications expect to find user-specific configuration files in the home directory. Without it, applications may not function correctly or may revert to default settings, which might not be suitable for the user.

3. Permissions and Access: The user will not have a private space to manage their files, which can lead to confusion and potential security issues, as they may inadvertently access or modify system files or other users' files.

Example Without -m

If you run the following command:

sudo useradd newuser

The user newuser will be created, but without a home directory. You can check this by listing the /home directory:

ls /home

You will not see a newuser directory listed, indicating that the home directory was not created.

Conclusion

It's generally a best practice to always use the -m option when creating new users to ensure they have a proper environment to work in. If you accidentally create a user without a home directory, you can create one manually using the mkdir command and set the appropriate permissions, but this is an extra step that can be avoided by using -m from the start.

If you have more questions or need further clarification, feel free to ask!