Server lifecycle

A server, during his lifecycle, passes along multiple states and stages before becoming available and ready to use.

Server states

Available

A server is healthy and ready to be used in a new provisioning operation.

Available_reserved

State available_reserved can be set on a server that is in the available state but is reserved for a specific user.

Used

A server is already used and cannot be used in a new provisioning process in the current state.

Registering

A new server when is being first added to the application, it passes through a complex process so the system is aware of its hardware components, configuration etc. For this a live, lightweight and custom linux image is being booted up and a series of scripts are being ran.

Cleaning

A server under the cleaning state is in the middle of a de-provision operation. The same live linux image runs some clean-up scripts during this stage, making the server ready for a new provisioning operation.

Defective

When specific issues occur with a server or hardware faults are present, each server can be marked as defective, from its page. When in defective state, a server cannot pass into the Used state.

Used_registering

A server is in the used_registering state, when a already used server is passed through the registering process and it is expected to be in directly in the used state, after the registering process is finished.

Decommissioned

The decommissioning state describes a server that has been basically removed from the application and cannot be used unless re-added again (going back through the first server cycle described below).

Interact with the server states

All the servers in all their states, can be seen in the Server type utilization report page.

../_images/server_status_list.pngserver lifecycle

Administrator can interact with the server states. He can do so by accessing the server page, going to the Server status section and pressing the desired buttons. From here, the server can be moved into available, unavailable, used, defective or removed_from_rack

../_images/server_status_buttons.pngserver lifecycle

The registration and decommissioning processes can be triggered from the specific section.

../_images/re-register_or_decomission.pngserver lifecycle

Server cycles

1. Adding a server and using it

When a new server is being first added into the application it first passes through the registering process. If the registering processes succeeds, then it goes into the unavailable state. From here, it can be set manually in the available state. From here on, the server can be selected and used in a provision process.

../_images/server_lifecycle_1.svgserver lifecycle

2. Modifying and re-registering a used server

When modifications need to be done to a server in state, the re-register processes can be issued to an active server.

../_images/server_lifecycle_2.svgserver lifecycle

3. Releasing a server and using it again

The following diagram shows the states of a server from its release to its reutilisation.

../_images/server_lifecycle_3.svgserver lifecycle

4. Marking a server as defective

The process of marking a server as defective is a manual one. Once a server is diagnosed as unhealthy, the below button can be used to mark it as defective. Note that the server must not be in Used state when tagging it as defective.

../_images/defective.pngserver lifecycle

During the server recovery, the notes section can be used to note down the fault,current status and other details.

../_images/notes.pngserver lifecycle

After the server is repaired, it can be set to available again using the Available button.

../_images/available.pngserver lifecycle

The following diagram shows the states of a server from marking it as defective to setting it as available again and then being used.

../_images/server_lifecycle_4.svgserver lifecycle