Users and Groups

In this week, we will again use our virtual machine. This time, we will be creating two users and granting selected permissions from one user to the other.

First, create a new user with “useradd -m ”. Then, repeat the command for a second user. Set a password for each user with “passwd ”.

Next, we will create a group for our users with “groupadd ”. Add your users to the group with “usermod -G ”.

Test out logging in as your first user with the command “su – ”. Next, we will create three files using the following commands:

• echo “first file” > file1
• echo “second file” > file2
• echo “third file” > file3

You can validate the contents of file1 with “cat file1”. Let’s validate the file permissions of our files with “ls -l”. Take a screenshot of the output. Every file has nine permissions, ignoring the first one. The first three are for the user, the next three are for the group, and the final three are for others.

Next, we are going to adjust permissions so that:

• File1 is only readable and writeable to user1
• File2 is readable and writeable to user1 and members of the group to which you added both users 
• File3 is readable by all users, but writeable only by user1

To make these changes, you’ll use the “chmod” command to adjust permissions, and you’ll need to add file2 to the group our users are in using “chown : file2”. To use the chmod command, there are two syntaxes: octal syntax and letter syntax. We are going to use the letter syntax in these examples. If you know octal syntax, feel free to use that instead.

The format is going to be “chmod ”. The value will be one of u for user, g for group, o for others, or a for all. The will be + to add permissions and – to remove permissions. The will be any of r for read, w for write, or x for execute. Set the permissions of the files to the bulleted list above. Validate your permissions with “ls -l” and take a screenshot of the output.

Then, switch to the second user account and verify the permissions using the following commands.

• cat file1
• cat file2
• cat file3
• echo “first file” > file1
• echo “second file” > file2
• echo “third file” > file3

Take a screenshot of the results of these commands. If the results don’t match expectations, you can switch back to your user1 and adjust permissions again to get it right.

In your submission, include:

• Screenshot of “ls -l” output before changing permissions
• Screenshot of “ls -l” output after changing permissions
• Screenshot of the validation commands as user2

Parameters

• The assignment should be double-spaced, 12-point Times New Roman font, with one-inch margins
• Use APA for citing references and quotations
• See the assignment rubric below for more details