QA:Testcase CoreOS switch stream

Description

This tests whether an existing Fedora CoreOS instance running on the stable stream can switch to the next stream.

Setup

1. Have access to a (or install a new) FCOS instance running the stable stream.

How to test

1. Verify that your FCOS system is running on stable:

   $ sudo rpm-ostree status
   State: idle
   Deployments:
   ● ostree://fedora:fedora/x86_64/coreos/stable
                      Version: 32.20201018.3.0 (2020-11-02T20:54:53Z)
                       Commit: a6f3e91ad6e0b8e132769c1694ed9b747a339c04e4e6256fce3afd81c85e1f1f
                 GPGSignature: Valid signature by 97A1AE57C3A2372CCA3A4ABA6C13026D12C944D0
   

   The black circle ● shows the currently booted tree (if you see multiple deployments available). The current tree should show fedora/x86_64/coreos/stable. The rest of the lines may differ from the above output.

2. Follow the Update Streams documentation to switch your system to the next stream.
   • A package difference should be displayed during the switch operation for you to review.
3. Reboot
4. Verify that your system is now running on the next stream:

   $ sudo rpm-ostree status
   State: idle
   Deployments:
   ● State: idle
   AutomaticUpdatesDriver: Zincati
     DriverState: active; periodically polling for updates (last checked Sun 2021-04-25 17:44:22 UTC)
   Deployments:
   * ostree://fedora:fedora/x86_64/coreos/next
                      Version: 34.20210418.1.0 (2021-04-21T14:49:53Z)
                       Commit: 7e6668b2ed6cc3693077e2c10e217accbe3affeb10208ea1a5959f0758398343
                 GPGSignature: Valid signature by 8C5BA6990BDB26E19F2A1A801161AE6945719A39
     ostree://fedora:fedora/x86_64/coreos/stable
                      Version: 32.20201018.3.0 (2020-11-02T20:54:53Z)
                       Commit: a6f3e91ad6e0b8e132769c1694ed9b747a339c04e4e6256fce3afd81c85e1f1f
                 GPGSignature: Valid signature by 97A1AE57C3A2372CCA3A4ABA6C13026D12C944D0
   

   The current tree should show fedora/x86_64/coreos/next. The rest of the lines may differ from the above output.

Expected Results

1. The system successfully reboots and runs on the next stream.
2. The system is functional (you can connect the same way as before, your services are running as before).
3. The linked documentation is clear, all steps are understandable, and nothing important is missing from it.

Optional

1. Before switching to the next stream, try for example creating containers or configuring a service and verify that the changes are successfully carried over after switching.
2. After switching to the next stream, attempt both a temporary and a permanent manual rollback. After each rollback, verify that your system booted with the correct filesystem tree using sudo rpm-ostree status.
3. There is another test case you can follow which uses the same "switch stream" preparation already done here. So you'd only need to follow the final bootloader-related steps to complete it.