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Machine

The Machine is the central model in Digital Rebar Provision. It represents a bare-metal or virtual system managed by DRP, identified by a unique immutable UUID assigned at creation time. The machine's primary purpose is to map an incoming IP address to a BootEnv that provides rendered templates for booting and configuring the system.

Machines operate in two execution modes. In Workflow mode, DRP drives the machine through a provisioning pipeline: a Workflow sets the Stage and Tasks list, and the machine agent requests Job objects to execute each task in sequence. In WorkOrder mode, the machine has completed initial provisioning and accepts WorkOrder objects for post-provisioning operations such as configuration changes, maintenance actions, and CI/CD tasks. The WorkOrderMode field controls which mode is active.

Each machine maintains an ordered list of Profile references that form a parameter inheritance chain. When resolving a parameter value, DRP searches the machine's own embedded parameters first, then each profile in list order, and finally the global profile. This layered approach allows shared configuration through profiles while permitting per-machine overrides.

The HardwareAddrs field holds MAC addresses used for PXE boot identification, and the Address field tracks the IPv4 address for provisioning (automatically updated by DHCP when hardware addresses are present). The Arch field specifies the system architecture (amd64, arm64, and others) and determines which boot environment artifacts are served. The Fingerprint field contains DMI-based identification data (system serial number hashes, chassis serial number hashes, memory module identifiers, and cloud instance IDs) used to match and re-identify machines across reboots.

Machines can belong to a Pool Object for lifecycle management, where they transition through states such as Joining, Free, InUse, and Leaving. The Pool and PoolStatus fields track this membership. The Locked field prevents unauthorized modifications, and the Secret field controls token revocation for machine authentication.

A machine is defined by having the Meta field machine-role set to machine or self. For backwards compatibility, a machine without a machine-role metadata entry is considered a machine. Related machine-like models include Cluster and Resource Broker, which share the same underlying structure but serve different roles.

Metadata

Field Description Value
BaseContext: [context] Lets DRP know what the base context is for the machine when going back to a known context.
machine-role: [role] Set by DRP and should not be edited. It lets DRP know what the type of machine this object is. self, machine, cluster, or resource-broker
pipeline the name of the executed pipeline and set by DRP during pipeline execution to allow operators to trace jobs across a pipeline run.
pipeline-uuid A unique ID for each executed pipeline and set by DRP during pipeline execution to allow operators to trace jobs across a pipeline run.

Fields

Field Definition
Address The IPv4 address of the machine that should be used for PXE
purposes. Note that this field does not directly tie into DHCP
leases or reservations -- the provisioner relies solely on this
address when determining what to render for a specific machine.
Address is updated automatically by the DHCP system if
HardwareAddrs is filled out.

swagger:strfmt ipv4
Arch Arch is the machine architecture. It should be an arch that can
be fed into $GOARCH.
BootEnv The boot environment that the machine should boot into. This
must be the name of a boot environment present in the backend.
If this field is not present or blank, the global default bootenv
will be used instead.
Context Contexts contains the name of the current execution context.
An empty string indicates that an agent running on a Machine should be executing tasks,
and any other value means that an agent running with its context set for this value should
be executing tasks.
CurrentTask The index into the Tasks list for the task that is currently
running (if a task is running) or the next task that will run (if
no task is currently running). If -1, then the first task will
run next, and if it is equal to the length of the Tasks list then
all the tasks have finished running.

read only: true
Description Description is a string for providing a simple description
Fingerprint/CSNHash DMI.System.Manufacturer + DMI.System.ProductName + DMI.Chassis[0].SerialNumber, SHA256 hashed
Hash must not be zero-length to match. 25 points
swagger:strfmt byte
Fingerprint/CloudInstanceID Cloud-init file in /run/cloud-init/instance-data.json
String from ID of '.v1.cloud_name' + '.v1.instance_id'. 500 point match
Fingerprint/MemoryIds MemoryIds is an array of SHA256sums if the following fields in each
entry of the DMI.Memory.Devices array concatenated together:
* Manufacturer
* PartNumber
* SerialNumber
Each hash must not be zero length
Score is % matched.
Fingerprint/SSNHash DMI.System.Manufacturer + DMI.System.ProductName + DMI.System.SerialNumber, SHA256 hashed
Hash must not be zero-length to match. 25 points
swagger:strfmt byte
Fingerprint/SystemUUID DMI.System.UUID, not hashed. Must be non zero length and must be a non-zero UUID. 50 point match
HardwareAddrs HardwareAddrs is a list of MAC addresses we expect that the system might boot from.
This must be filled out to enable MAC address based booting from the various bootenvs,
and must be updated if the MAC addresses for a system change for whatever reason.
JobExitState The final disposition of the current job.
Can be one of "reboot","poweroff","stop", or "complete"
Other substates may be added as time goes on
JobResultErrors ResultErrors is a list of error from the task. This is filled in by the
task if it is written to do so. This tracks results without requiring
job logs.
JobState The state the current job is in. Must be one of "created", "failed", "finished", "incomplete"
Locked Locked indicates that changes to the Machine by users are not
allowed, except for unlocking the machine, which will always
generate an Audit event.
Meta Meta contains the meta data of the object.

The type of this field is a key / value map/dictionary.
The key type is string.
The value type is also string.

The general content of the field is undefined and can be an arbritary store.
There are some common known keys:

color - The color the UX uses when displaying
icon - The icon the UX uses when displaying
* title - The UX uses this for additional display information. Often the source of the object.

Specific Object types use additional meta data fields. These are described at:
https://docs.rackn.io/stable/redirect/?ref=rs_object_metadata
Name The name of the machine. This must be unique across all
machines, and by convention it is the FQDN of the machine,
although nothing enforces that.

required: true
swagger:strfmt hostname
OS OS is the operating system that the node is running in. It is updated by Sledgehammer and by
the various OS install tasks.
Params Params holds the values of parameters on the object.

The field is a key / value store of the parameters.
The key is the name of a parameter. The key is of type string.
The value is the value of the parameter. The type of the value is defined
by the parameter object. If the key doesn't reference a parameter, the
type of the object can be anything.

The system will enforce the named parameter's value's type.

Go calls the "anything" parameters as "interface {}". Hence, the type
of this field is a map[string]interface{}.
Pool Pool contains the pool the machine is in.
Unset machines will join the default Pool
PoolStatus PoolStatus contains the status of this machine in the Pool.
Values are defined in Pool.PoolStatuses
Profiles Profiles is an array of profiles to apply to this object in order when looking
for a parameter during rendering.
Runnable Runnable indicates that this is Runnable.
Secret Secret for machine token revocation. Changing the secret will invalidate
all existing tokens for this machine
Stage The stage that this is currently in.
TaskErrorStacks This list of previous task lists and current tasks to handle errors.
Upon completing the list, the previous task list will be executed.

This will be capped to a depth of 1. Error failures can not be handled.
TaskErrorStacks/CurrentJob CurrentJob is the job that presents this task stack
swagger:strfmt uuid
TaskErrorStacks/CurrentTask CurrentTask is the index in the task list in a previous errored task.
TaskErrorStacks/TaskList TaskList is the task list from a previous errored task.
Tasks The current tasks that are being processed.
Uuid The UUID of the machine.
This is auto-created at Create time, and cannot change afterwards.

swagger:strfmt uuid
WorkOrderMode WorkOrderMode indicates if the machine is action mode
Workflow Workflow is the workflow that is currently responsible for processing machine tasks.

The Name field should contain the FQDN of the node.

The machine object contains an Error field that represents errors encountered while operating on the machine. In general, these are errors pertaining to rendering the bootenv.

Note

When updating the params part of the embedded profile in the machine object, using the PUT method will replace the params map with the map from the input object. The PATCH API method will merge the params map in the input with the existing params map in the current machine object. The POST method on the params subaction will replace the map with the input version.

Job Monitoring

To get Websocket events for jobs for a specific machine, the machine_jobs.*.<uuid> register can be used.

Purge all Jobs for a Machine

To purge all Jobs for a Machine, make use of the drpcli jobs purge command:

Bash
drpcli jobs purge --machine UUID --jobs-to-keep 0 --complete-after 0s --fail-after 0s

Explanation of command:

Flag Explanation
--machine UUID replace UUID with the UUID of the machine you'd like to purge jobs from
--jobs-to-keep 0 do not retain any recent jobs from the purge
--complete-after 0s includes jobs that are marked as completed and are older than 0s
--fail-after 0s includes jobs that are marked as failed and are older than 0s

Effectively, this command removes all completed/failed jobs for a given machine by its UUID. Adjust the time flags (0s) to preserve recent jobs if necessary.