Guided Exercise: Customize a blueprint for post-installation tasks

Customize a blueprint by using the web console for post-installation tasks like adding users and SSH keys.

Outcomes

Customize a blueprint by using the web console for post-installation tasks like adding users and SSH keys.
1. Save the composer-test blueprint using the composer-cli command.
2. Configure a new user user1 with password redhat, and belongs to the wheel and users groups.
3. Configure an SSH key for the root user.
4. Push the modified composer-test blueprint, and confirm that your changes are applied.
5. Use the RHEL web console to create a QEMU qcow2 Image (.qcow2) using the customized blueprint.

The resulting image build should have user1 with sudo access (because of the wheel group), and it allows SSH for the root user with the correct key authentication.

Instructions

Save a copy of the composer-test blueprint and copy it to a new file before customizing it.
1. Open a terminal to the workstation machine.
2. Use this command to save a copy of the blueprint configuration file.
  [student@workstation ~]$ composer-cli blueprints save composer-test
  1. The file itself is in the TOML format (.toml) and can be edited in any text editor.
    
    [student@workstation ~]$ ls composer-test.toml ...
    
    Note: The name of the TOML file does not matter, it is optional that you rename the file to match the blueprint name.
3. Copy the file to the name composer-test-new.toml.
  [student@workstation ~]$ cp composer-test.toml composer-test-new.toml

Edit the file composer-test-new.toml in a local text editor to customize the blueprint.

Change the blueprint name (the name field) to "composer-test-new".
```
name = "composer-test-new"
...output omitted...
```

Add an SSH key for the root user. Use the key shown in this file excerpt.

[[customizations.sshkey]]
user = "root"
key = "ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQDGtUW3ismHyuCW4CDdTVOOOq6aySdtYenXFWWx7HJa4VTepkG00aaLId9ocra10hc+MB0GTJMCyabDv3i8NKdi6GDH/aOLVsp/Ewy8DEzZMBlJDCt4v2i4/wU4liw6KgEFkZs+5hnqU8d4QzldyGJ5onr+AGvFOKG68CS0BBl40Z1twf1HhCyx8k6nzD2ovlkxWRFZKPAFrtPCBVvQDkOfVFZF+lwzaSztgAjbFZ4A9jqQyUYx4kOJ5DtRef36ucdUdVQale0+8lICl7/gb142SPpYfhxe88/BJScLPRjvVNeu1TxRmoHtVazqnAoRxQYAn2MoI6AG+w6QuZf8f7aL LabGradingKey"

Note:
 If you try to copy/paste from here and meet an error, copy the SSH key from the contents of the file /home/student/.ssh/lab_rsa.pub on the workstation machine.

Generate an encrypted password string for the password redhat (enter redhat when prompted).
```
[student@workstation ~]$ python3 -c "import crypt, getpass; print(crypt.crypt(getpass.getpass(), crypt.METHOD_SHA512))"
Password:
$6$.......
```
1. The value of the encrypted string in the preceding output is different on your system.
2. Copy the encrypted password string you generated. You use it in the next step for the value of the password = field in the customizations.user section.
Add a new user to the blueprint by adding the following section to the file.
1. This section adds the user user1 with the password redhat.
2. Paste the copied encrypted password string value from the previous step in the password field within double quotes.
3. In the key field, use the SSH key you used for the root user in a previous step.
4. The user uses the public key of the student user and is part of groups users and wheel.
  [[customizations.user]] name = "user1" password = "<encrypted password string copied from previous step>" key = "<public SSH key for student user>" shell = "/usr/bin/bash" groups = ["users", "wheel"] uid = 1001

Save and close the file after you make the changes.

Push this new configuration to image builder:

[student@workstation ~]$ composer-cli blueprints push composer-test-new.toml

Refresh the RHEL web console and return to the Image Builder page. Verify that the new blueprint composite-test-new is visible.
Create a qemu2 image for the composer-test-new blueprint.
1. Click Create image button for the composer-test-new blueprint.
2. Select the Image output type as QEMU image (.qcow2) and then click Next.
3. Click Create.

Wait for about 5 minutes for the image creation to complete. Check the status from the command line.

[student@workstation hol001]$ composer-cli compose list
ID                                     Status     Blueprint           Version   Type
b50ccabb-3234-4bb8-b970-e5bd20754986   FINISHED    composer-test-new   0.0.1     qcow2
58ad5f0e-870e-482f-882d-3a727d3185fc   FINISHED   composer-test       0.0.0     tar
f24ce6c2-beba-41e6-b5e4-783bfdeeec70   FINISHED   composer-test       0.0.1     qcow2

Install the libguestfs-tools-c package as the grading script requires it to evalute your work. Enter the sudo password student when prompted.
```
[student@workstation ~]$ sudo dnf install -y libguestfs-tools-c
[sudo] password for student:
```

Run the grading script to verify your work.

[student@workstation ~]$ lab grade imagebuilder-customize
Grading lab.
SUCCESS Checking lab systems
...output omitted...
Overall lab grade: PASS

Note:
  If you run the script too early, the script fails as the image creation is not complete.

Optionally, download and test the image on the workstation machine.

Click Download image for the image created from the composer-test-new blueprint to download the image.
1. Select Save File and then click OK.
In a previous exercise you configured the workstation machine to run virtual machines. If you have not configured it, then configure it by following the steps in the previous exercise.

Verify that the image is downloaded.

[student@workstation hol001]$ ls ~/Downloads/
b50ccabb-3234-4bb8-b970-e5bd20754986-disk.qcow2  d7c11834-cc76-474d-9ace-68a071cf89ff-disk.qcow2

The file names in the preceding output are different on your system.

Copy the image to the default storage pool. Make sure to copy the correct file (the latest one).
```
[student@workstation ~]$ sudo cp /home/student/Downloads/b50ccabb-3234-4bb8-b970-e5bd20754986-disk.qcow2 /var/lib/libvirt/images/
[sudo] password for student:
```
1. The file name in the preceding output is different on your system.

Test the image using the following command. The commands creates a virtual machine with the name RHEL9Lab2.

[student@workstation ~]$ sudo virt-install --name RHEL9Lab3 --memory 2048 --vcpus 2 --os-variant rhel9.0 --import --disk  /var/lib/libvirt/images/b50ccabb-3234-4bb8-b970-e5bd20754986-disk.qcow2
...output omitted...
Starting install...
Creating domain...
Domain is still running. Installation may be in progress.
Waiting for the installation to complete.

You can use ctrl+c to quit out of the running command.

On the workstation GUI, search for Virtual Machine Manager.
1. Open the Virtual Machine Manager application. Enter the student password and click Authenticate.
2. Verify that the RHEL9Lab3 VM is visible.
3. Click the open button to view the console.
Verify you can log in with the username user1 and password redhat.
Switch to the terminal on workstation. List the virtual machines which are running.
```
[student@workstation ~]$ sudo virsh list
[sudo] password for student:
Id   Name        State
---------------------------
1    RHEL9Lab2   running
2    RHEL9Lab3   running
```
1. You can have only one machine running if you have not launched the RHEL9Lab2 in the previous exercise as it was an optional step.

Retrieve the IP of the RHEL9Lab3 VM.

[student@workstation ~]$ sudo virsh domifaddr RHEL9Lab3
Name       MAC address          Protocol     Address
-------------------------------------------------------------------------------
vnet1      52:54:00:4d:38:df    ipv4         192.168.122.2/24

The IP address can be different on your system.

Verify you can log in to the RHEL9Lab3 VM as the root user by using the SSH key of the student user.

[student@workstation ~]$ ssh root@192.168.122.2
Warning: Permanently added '192.168.122.2' (ED25519) to the list of known hosts.
...output omitted...
[root@localhost ~]#

Verify that user1 is part of groups wheel and users.

[root@localhost ~]# su - user1
Last login: Thu Nov  2 10:20:17 EDT 2023 on tty1
[user1@localhost ~]$ id
... groups=1001(user1),10(wheel),100(users) ...

Verify that user1 can run privileged commands with sudo. Enter redhat as the sudo password when prompted.

[user1@localhost ~]$ sudo systemctl status chronyd
...output omitted...
[sudo] password for user1:
● chronyd.service - NTP client/server
Loaded: loaded (/usr/lib/systemd/system/chronyd.service; enabled; vendor preset: enabled)
Active: active (running) since Thu 2023-11-02 10:19:20 EDT; 15min ago
...output omitted...