..
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..
   [TODO] Most of this file should be generated in #146

.. _lm_config:

Configuration
*************

The following section will exaplin all configuration parameters.

.. _lm_conf_measurement_units:

Measurement units
=================

This section provides an overview of the measurement units used within the configuration and explains how they ensure consistent representation of values within the system.

.. _lm_conf_time_intervals:

Time Intervals
--------------

All time values in the **Launch Manager** configuration are specified in **seconds**. When a fraction of a second is required, a **decimal point** must be used.

For example:

* ``0.5`` represents a time interval of 500 milliseconds.
* ``1.5`` represents a time interval of 1500 milliseconds.

Using a consistent unit prevents ambiguity and makes the configuration values easier to compare and understand.

.. _lm_conf_memory:

Memory
------

All configuration values representing memory sizes are specified in **bytes**.

For example:

* ``1000`` represents one kilobyte (kB), following the **SI** standard.
* ``1024`` represents one kibibyte (KiB), following the **IEC** standard.

Storing memory values in bytes ensures that all size-related settings remain precise and unambiguous.

.. _lm_conf_configuration_schema:

Configuration schema
====================

This section provides a detailed description of the **Launch Manager** configuration schema. This section is organized to facilitate understanding, starting with common building blocks and then proceeding to the top-level configuration properties.

The **Launch Manager** configuration leverages reusable definitions, primarily found within the standard ``$defs`` object. These reusable types are the fundamental building blocks of the **Launch Manager** configuration. A thorough understanding of these types will simplify comprehension of the overall configuration structure and the interaction between different settings.

.. _lm_conf_reusable_types:

Reusable Types
--------------

The following sections describe the reusable types that form the basis of the **Launch Manager** configuration.

.. _lm_conf_alive_supervision_object_:

alive_supervision (object)
^^^^^^^^^^^^^^^^^^^^^^^^^^

**Description:**
  Defines a reusable type that contains configuration parameters for alive supervision, which helps monitor the health and responsiveness of components.

**Properties:**

* **evaluation_cycle** (number, optional)
    * **Description:** Specifies the length, in seconds (e.g., ``0.5`` for 500 milliseconds), of the time window used by the **Launch Manager** to assess incoming alive supervision reports from components.
    * **Constraint:** Must be greater than 0.

.. _lm_conf_watchdog_object_:

watchdog (object)
^^^^^^^^^^^^^^^^^

**Description:**
  Defines a reusable type that contains configuration parameters for the external watchdog device, used to monitor the overall system health and initiate resets if necessary.

**Properties:**

* **device_file_path** (string, optional)
    * **Description:** Specifies the absolute path to the external watchdog device file (e.g., ``/dev/watchdog``).
* **max_timeout** (number, optional)
    * **Description:** Specifies the maximum timeout value, in seconds (e.g., ``0.5`` for 500 milliseconds), that the **Launch Manager** configures on the external watchdog during startup. The external watchdog uses this timeout as the deadline for receiving periodic alive reports from the **Launch Manager**.
    * **Constraint:** Must be 0 or greater.
* **deactivate_on_shutdown** (boolean, optional)
    * **Description:** Specifies whether the **Launch Manager** disables the external watchdog during shutdown. When set to ``true``, the watchdog is deactivated; when ``false``, it remains active, potentially triggering a reset if the shutdown is prolonged.
* **require_magic_close** (boolean, optional)
    * **Description:** Specifies whether the **Launch Manager** performs a defined shutdown sequence to inform the external watchdog that the shutdown is intentional and to prevent a watchdog-initiated reset. When ``true``, the magic close sequence is performed; when ``false``, it is not, which might lead to an unintentional reset.

.. _lm_conf_recovery_action_object_:

recovery_action (object)
^^^^^^^^^^^^^^^^^^^^^^^^

**Description:**
  Defines a reusable type that specifies recovery actions to execute when an error or failure occurs. This object must contain exactly one of the defined recovery actions.

**Properties:**

* **restart** (object, optional)
    * **Description:** Defines a recovery action that restarts the POSIX process associated with this component.
    * **Properties:**
        * **number_of_attempts** (integer, optional)
            * **Description:** Specifies the maximum number of restart attempts before the **Launch Manager** concludes that recovery cannot succeed for the component.
            * **Constraint:** Must be 0 or greater.
        * **delay_before_restart** (number, optional)
            * **Description:** Specifies the delay duration, in seconds (e.g., ``0.25`` for 250 milliseconds), that the **Launch Manager** waits before initiating a restart attempt.
            * **Constraint:** Must be 0 or greater.
* **switch_run_target** (object, optional)
    * **Description:** Defines a recovery action that switches to a different **Run Target**. This can be a new **Run Target** or the current one to retry its activation.
    * **Properties:**
        * **run_target** (string, optional)
            * **Description:** Specifies the name of the **Run Target** that the **Launch Manager** should switch to upon failure.

.. _lm_conf_run_target_object_:

run_target (object)
^^^^^^^^^^^^^^^^^^^

**Description:**
  Defines a reusable type that specifies configuration parameters for a **Run Target**, outlining a particular operational mode for the system.

**Properties:**

* **description** (string, optional)
    * **Description:** Specifies a user-defined description of the **Run Target's** purpose or operational context.
* **depends_on** (array of strings, optional)
    * **Description:** Specifies the names of components and other **Run Targets** that must be successfully activated when this **Run Target** is activated. This defines the dependencies for a given operational mode.
    * **Items:** Each item is a string specifying the name of a component or **Run Target** on which this **Run Target** depends.
* **transition_timeout** (number, optional)
    * **Description:** Specifies the time limit, in seconds (e.g., ``1.5`` for 1500 milliseconds), for the **Run Target** transition to complete. If this limit is exceeded, the transition is considered failed.
    * **Constraint:** Must be greater than 0.
* **recovery_action** (object, optional)
    * **Description:** Specifies the recovery action to execute when a component assigned to this **Run Target** fails. This action is limited to ``switch_run_target`` operations.
    * **Reference:** This property refers to the `recovery_action` reusable type defined in this schema, specifically enforcing the ``switch_run_target`` option.

.. _lm_conf_component_properties_object_:

component_properties (object)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

**Description:**
  Defines a reusable type that captures essential characteristics of a software component, influencing how the **Launch Manager** interacts with it.

**Properties:**

* **binary_name** (string, optional)
    * **Description:** Specifies the relative path of the executable file within the directory defined by ``deployment_config.bin_dir``. The final executable path will be resolved as ``{deployment_config.bin_dir}/{binary_name}``. Example values include simple filenames (e.g., ``test_app1``) or paths to executables within subdirectories (e.g., ``bin/test_app1``).
* **application_profile** (object, optional)
    * **Description:** Defines the application profile that specifies the runtime behavior and capabilities of this component, particularly concerning its interaction with the **Launch Manager**.
    * **Properties:**
        * **application_type** (string, optional)
            * **Description:** Specifies the level of integration between the component and the **Launch Manager**.
            * **Allowed Values:**
                * ``"Native"``: Indicates no integration with the **Launch Manager**.
                * ``"Reporting"``: Implies the component uses **Launch Manager** lifecycle APIs for basic reporting.
                * ``"Reporting_And_Supervised"``: Implies the component uses lifecycle APIs and sends alive notifications to the **Launch Manager**.
                * ``"State_Manager"``: Implies the component uses lifecycle APIs, sends alive notifications, and has permission to change the active **Run Target**.
        * **is_self_terminating** (boolean, optional)
            * **Description:** Indicates whether the component is designed to terminate automatically once its planned tasks are completed (``true``), or if it is expected to remain running until explicitly requested to terminate by the **Launch Manager** (``false``).
        * **alive_supervision** (object, optional)
            * **Description:** Defines the configuration parameters used for monitoring the "aliveness" of the component.
            * **Reference:** This property refers to the ``alive_supervision`` reusable type defined in this schema.
            * **Properties:** (These properties are also inherited from ``alive_supervision`` but are listed here for quick reference and clarity on the local context.)
                * **reporting_cycle** (number, optional)
                    * **Description:** Specifies the duration, in seconds (e.g., ``0.5`` for 500 milliseconds), of the time interval used to verify that the component sends alive notifications within the expected time frame.
                    * **Constraint:** Must be greater than 0.
                * **failed_cycles_tolerance** (integer, optional)
                    * **Description:** Specifies the maximum number of consecutive reporting cycle failures. Once the number of failed cycles exceeds this maximum, the **Launch Manager** will trigger the configured recovery action.
                    * **Constraint:** Must be 0 or greater.
                * **min_indications** (integer, optional)
                    * **Description:** Specifies the minimum number of checkpoints that must be reported within each configured ``reporting_cycle``.
                    * **Constraint:** Must be 0 or greater.
                * **max_indications** (integer, optional)
                    * **Description:** Specifies the maximum number of checkpoints that may be reported within each configured ``reporting_cycle``.
                    * **Constraint:** Must be 0 or greater.
* **depends_on** (array of strings, optional)
    * **Description:** Specifies the names of components that this component depends on. Each specified dependency must be initialized and reach its **Ready State** before the **Launch Manager** will start this component. This ensures proper startup order.
    * **Items:** Each item is a string specifying the name of a component on which this component depends.
* **process_arguments** (array of strings, optional)
    * **Description:** Specifies an ordered list of command-line arguments to be passed to the component at startup.
    * **Items:** Each item is a string specifying a single command-line argument token as a UTF-8 string; the order of arguments is preserved.
* **ready_condition** (object, optional)
    * **Description:** Defines the set of conditions that determine when the component completes its initializing state and enters the **Ready State**.
    * **Properties:**
        * **process_state** (string, optional)
            * **Description:** Specifies the required state of the component's POSIX process for it to be considered ready.
            * **Allowed Values:**
                * ``"Running"``: The process has started and reached its running state.
                * ``"Terminated"``: The process has started, reached its running state, and then terminated successfully.

.. _lm_conf_deployment_config_object_:

deployment_config (object)
^^^^^^^^^^^^^^^^^^^^^^^^^^

**Description:**
  Defines a reusable type that contains configuration parameters specific to a particular deployment environment or system setup.

**Properties:**

* **ready_timeout** (number, optional)
    * **Description:** Specifies the maximum time, in seconds (e.g., ``0.25`` for 250 milliseconds), allowed for the component to reach its **Ready State**. The timeout is measured from when the component's process is created until the ready conditions specified in ``component_properties.ready_condition`` are met.
    * **Constraint:** Must be greater than 0.
* **shutdown_timeout** (number, optional)
    * **Description:** Specifies the maximum time, in seconds (e.g., ``0.75`` for 750 milliseconds), allowed for the component to terminate after it receives a SIGTERM signal from the **Launch Manager**. The timeout is measured from when the **Launch Manager** sends the SIGTERM signal until the operating system notifies the **Launch Manager** that the child process has terminated.
    * **Constraint:** Must be greater than 0.
* **environmental_variables** (object, optional)
    * **Description:** Defines the set of environment variables passed to the component at startup.
    * **Additional Properties:** Each key represents an environment variable name, and its value (a string) specifies the environment variable's value. An empty string is allowed and represents an intentionally empty environment variable.
* **bin_dir** (string, optional)
    * **Description:** Specifies the absolute filesystem path to the directory where the component's executable is installed.
* **working_dir** (string, optional)
    * **Description:** Specifies the directory to be used as the working directory for the component during execution.
* **ready_recovery_action** (object, optional)
    * **Description:** Specifies the recovery action to execute when the component fails to reach its **Ready State** within the configured ``ready_timeout``. This action is limited to ``restart`` operations.
    * **Reference:** This property refers to the ``recovery_action`` reusable type defined in this schema, specifically enforcing the ``restart`` option.
* **recovery_action** (object, optional)
    * **Description:** Specifies the recovery action to execute when the component malfunctions after successfully reaching its **Ready State**. This action is limited to ``switch_run_target`` operations.
    * **Reference:** This property refers to the ``recovery_action`` reusable type defined in this schema, specifically enforcing the ``switch_run_target`` option.
* **sandbox** (object, optional)
    * **Description:** Defines the sandbox configuration parameters that isolate and constrain the component's runtime execution, enhancing system security and stability.
    * **Properties:**
        * **uid** (integer, optional)
            * **Description:** Specifies the POSIX user ID (UID) under which this component executes.
            * **Constraint:** Must be 0 or greater.
        * **gid** (integer, optional)
            * **Description:** Specifies the primary POSIX group ID (GID) under which this component executes.
            * **Constraint:** Must be 0 or greater.
        * **supplementary_group_ids** (array of integers, optional)
            * **Description:** Specifies the list of supplementary POSIX group IDs (GIDs) assigned to this component. These provide additional access permissions.
            * **Items:** Each item is an integer specifying a single supplementary POSIX group ID (GID).
            * **Constraint:** Each item must be 0 or greater.
        * **security_policy** (string, optional)
            * **Description:** Specifies the security policy or confinement profile name (such as an SELinux or AppArmor profile) assigned to the component, dictating its operating privileges.
        * **scheduling_policy** (string, optional)
            * **Description:** Specifies the scheduling policy applied to the component's initial thread. Supported values correspond to OS-defined policies (e.g., ``SCHED_FIFO``, ``SCHED_RR``, ``SCHED_OTHER``). Custom string values may also be supported depending on the operating system.
        * **scheduling_priority** (integer, optional)
            * **Description:** Specifies the scheduling priority applied to the component's initial thread, influencing its allocation of CPU time.
        * **max_memory_usage** (integer, optional)
            * **Description:** Specifies the maximum amount of memory, in bytes, that the component is permitted to use during runtime.
            * **Constraint:** Must be greater than 0.
        * **max_cpu_usage** (integer, optional)
            * **Description:** Specifies the maximum CPU usage limit for the component, expressed as a percentage (%) of total CPU capacity.
            * **Constraint:** Must be greater than 0.

.. _lm_conf_launch_manager_root_properties:

Launch Manager Root Properties
------------------------------

The top-level configuration of the **Launch Manager** is structured into several distinct sections, each serving a specific purpose in defining the system's behavior and managed components. While reusable types provide the foundational building blocks, these root properties orchestrate their application to form a complete and functional configuration.

A significant portion of the configuration is dedicated to defining default behaviors and managing the primary entities:
The ``defaults`` section allows users to establish system-wide default configuration parameters that can be inherited by components and **Run Targets**, thereby reducing repetitive configurations.
The ``components`` section defines the specific software components managed by the **Launch Manager**, with each component leveraging the ``component_properties`` and ``deployment_config`` reusable types to detail its characteristics and operational environment.
The ``run_targets`` section specifies all available **Run Targets**, where each **Run Target** is an instantiation of the ``run_target`` reusable type, grouping components into operational modes.

Beyond these core sections, several other crucial properties govern the overall operation of the **Launch Manager**:
The ``schema_version`` property ensures compatibility by indicating the schema version used for the configuration file.
The ``initial_run_target`` explicitly defines which **Run Target** the **Launch Manager** must activate upon startup.
The ``fallback_run_target`` provides a specialized **Run Target** to be activated when all other recovery attempts for normal **Run Targets** have been exhausted. This particular **Run Target** does not include a ``recovery_action`` property, as it represents the ultimate state of system recovery; if its activation also fails, an external watchdog mechanism will be triggered.
The ``watchdog`` property configures the external watchdog device used for monitoring the **Launch Manager** itself.
The ``alive_supervision`` property defines the global evaluation cycle parameters for monitoring processes launched by the **Launch Manager**.

With this overview in mind, let us now examine each root configuration property in detail.

.. _lm_conf_schema_version_integer_required_:

schema_version (integer, required)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

**Description:**
  Specifies the schema version number that the **Launch Manager** uses to determine how to parse and validate this configuration file.
**Allowed Value:**
  ``1``

.. _lm_conf_defaults_object_optional_:

defaults (object, optional)
^^^^^^^^^^^^^^^^^^^^^^^^^^^

**Description:**
  Defines default configuration values that components and **Run Targets** inherit unless they provide their own overriding values. Settings specified here apply globally to all components and **Run Targets**, reducing redundant configurations.

**Properties:**

* **component_properties** (object, optional)
    * **Description:** Defines default component property values applied to all components unless overridden in individual component definitions.
    * **Reference:** This property refers to the ``component_properties`` reusable type defined in this schema.
* **deployment_config** (object, optional)
    * **Description:** Defines default deployment configuration values applied to all components unless overridden in individual component definitions.
    * **Reference:** This property refers to the ``deployment_config`` reusable type defined in this schema.
* **run_target** (object, optional)
    * **Description:** Defines default **Run Target** configuration values applied to all **Run Targets** unless overridden in individual **Run Target** definitions.
    * **Reference:** This property refers to the ``run_target`` reusable type defined in this schema.
* **alive_supervision** (object, optional)
    * **Description:** Defines default alive supervision configuration values. These values are used unless a global ``alive_supervision`` configuration is explicitly specified at the root level of the configuration file.
    * **Reference:** This property refers to the ``alive_supervision`` reusable type defined in this schema.
* **watchdog** (object, optional)
    * **Description:** Defines default watchdog configuration values. These values are applied to all watchdogs unless overridden in individual watchdog definitions.
    * **Reference:** This property refers to the ``watchdog`` reusable type defined in this schema.

.. _lm_conf_components_object_optional_:

components (object, optional)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

**Description:**
  Defines the software components managed by the **Launch Manager**. Each property name within this object serves as a unique identifier for a component, and its corresponding value contains the component's specific configuration.

**Pattern Properties:** Keys must be valid identifiers (alphanumeric characters, underscores, and hyphens).

* **Component Definition** (object)
    * **Description:** Defines an individual component's configuration properties and deployment settings.
    * **Properties:**
        * **description** (string, optional)
            * **Description:** Specifies a human-readable description of the component's purpose.
        * **component_properties** (object, optional)
            * **Description:** Defines specific component properties for this component. Any properties not explicitly specified here will be inherited from ``defaults.component_properties``.
            * **Reference:** This property refers to the ``component_properties`` reusable type defined in this schema.
        * **deployment_config** (object, optional)
            * **Description:** Defines deployment configuration for this component. Any properties not explicitly specified here will be inherited from ``defaults.deployment_config``.
            * **Reference:** This property refers to the ``deployment_config`` reusable type defined in this schema.

.. _lm_conf_run_targets_object_optional_:

run_targets (object, optional)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

**Description:**
  Defines the **Run Targets** that represent different operational modes of the system. Each property name within this object serves as a unique identifier for a **Run Target**, and its corresponding value contains the **Run Target's** specific configuration.

**Pattern Properties:** Keys must be valid identifiers (alphanumeric characters, underscores, and hyphens).

* **Run Target Definition** (object)
    * **Description:** Defines an individual **Run Target's** configuration, specifying the components and dependencies that constitute a particular operational mode.
    * **Reference:** This property refers to the ``run_target`` reusable type defined in this schema.

.. _lm_conf_initial_run_target_string_required_:

initial_run_target (string, required)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

**Description:**
  Specifies the name of the **Run Target** that the **Launch Manager** activates during its startup sequence. This name must precisely match a **Run Target** defined within the ``run_targets`` section.

.. _lm_conf_fallback_run_target_object_optional_:

fallback_run_target (object, optional)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

**Description:**
  Defines the fallback **Run Target** configuration. The **Launch Manager** activates this **Run Target** when all recovery attempts for other **Run Targets** have been exhausted. This specific **Run Target** does not include a ``recovery_action`` property, as it represents the final state; if its activation also fails, the external watchdog will be triggered.

**Properties:**

* **description** (string, optional)
    * **Description:** Specifies a human-readable description of the fallback **Run Target**.
* **depends_on** (array of strings, required)
    * **Description:** Specifies the names of components and **Run Targets** that must be activated when this fallback **Run Target** is activated.
    * **Items:** Each item is a string specifying the name of a component or **Run Target** upon which this **Run Target** depends.
* **transition_timeout** (number, optional)
    * **Description:** Specifies the time limit, in seconds (e.g., ``1.5`` for 1500 milliseconds), for the **Run Target** transition. If this limit is exceeded, the transition is considered failed.
    * **Constraint:** Must be greater than 0.

.. _lm_conf_alive_supervision_object_optional_:

alive_supervision (object, optional)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

**Description:** Defines the global alive supervision configuration parameters used to monitor component health. If specified, this configuration will override any default values set in ``defaults.alive_supervision``.
**Reference:** This property refers to the ``alive_supervision`` reusable type defined in this schema.

.. _lm_conf_watchdog_object_optional_:

watchdog (object, optional)
^^^^^^^^^^^^^^^^^^^^^^^^^^^

**Description:** Defines the global external watchdog device configuration used by the **Launch Manager**. If specified, this configuration will override any default values set in ``defaults.watchdog``.
**Reference:** This property refers to the ``watchdog`` reusable type defined in this schema.

.. _lm_conf_default_values:

Default Values
==============

The **Launch Manager** configuration extensively utilizes the concept of default values to streamline the configuration process and simplify initial setup. The fundamental principle is that even if a specific configuration value is not explicitly provided by the user, a default value will always be applied, ensuring a complete and valid configuration.

To achieve this robust defaulting mechanism, the **Launch Manager** employs two distinct levels of default values:

1. **User-Defined Defaults:** These are specified within the ``defaults`` section of the **Launch Manager** configuration. Users can define a set of configuration options here, which will be applied if those options are not provided at a more specific level within the configuration (e.g., within an individual component, a **Run Target**, or at the root level for properties like ``alive_supervision`` or ``watchdog``).
2. **S-CORE Standard Defaults:** These represent a second tier of default values, provided by the S-CORE standard itself. The purpose of these defaults is to ensure a valid configuration value is available even if an option is entirely absent from both its specific definition and the user-defined ``defaults`` section.

The S-CORE standard defaults are particularly beneficial during the development phase. They allow developers to concentrate on core tasks without needing to meticulously define every configuration option, as a functional default is guaranteed.

.. _lm_conf_s_core_standard_defaults:

S-CORE Standard Defaults
------------------------

The **Launch Manager** guarantees the availability of these specific default values, which are applied when no corresponding configuration is found in the explicit definition of a property (e.g., within a component's ``deployment_config``, a **Run Target's** settings, or a root-level property) or within the user-defined ``defaults`` section.

The full, canonical definitions for these S-CORE standard defaults are provided in separate JSON files, shown below:

alive_supervision
  Defines default values for ``alive_supervision`` properties, governing the behavior of reporting and supervision mechanisms.

  .. dropdown:: alive_supervision_defaults.json

     .. literalinclude:: ../../../../src/launch_manager_daemon/config/config_schema/default_values/alive_supervision_defaults.json
        :language: json

watchdog
  Defines default values for ``watchdog`` properties.

  Please note that an empty object (``{}``) for ``watchdog`` signifies that the **Launch Manager** will disable watchdog functionality by default.

  .. dropdown:: watchdog_defaults.json

     .. literalinclude:: ../../../../src/launch_manager_daemon/config/config_schema/default_values/watchdog_defaults.json
        :language: json

run_target
  Defines default values for ``run_target`` properties, including the basic structure, behavior, and recovery actions for a **Run Target**.

  .. dropdown:: run_target_defaults.json

     .. literalinclude:: ../../../../src/launch_manager_daemon/config/config_schema/default_values/run_target_defaults.json
        :language: json

component_properties
  Defines default values for ``component_properties``, which specify fundamental characteristics and operational parameters for individual components.

  .. dropdown:: component_properties_defaults.json

     .. literalinclude:: ../../../../src/launch_manager_daemon/config/config_schema/default_values/component_properties_defaults.json
        :language: json

deployment_config
  Defines default values for ``deployment_config``, covering aspects of how a component is deployed and managed, such as resource limits and recovery.

  .. dropdown:: deployment_config_defaults.json

     .. literalinclude:: ../../../../src/launch_manager_daemon/config/config_schema/default_values/deployment_config_defaults.json
        :language: json

fallback_run_target
  The ``fallback_run_target`` is a critical configuration option within the **Launch Manager**.

  While the S-CORE standard does not currently provide an official default JSON configuration for ``fallback_run_target``, its behavior when unconfigured is important to understand.

  If ``fallback_run_target`` is not explicitly configured by the user, the Bazel target responsible for generating configuration files will create a **Run Target** that does not depend on any component. In this specific scenario, the ``fallback_run_target`` will effectively cause all components to shut down, with the exception of the **Launch Manager** itself. Understanding this default behavior is crucial for ensuring the desired system state during operation.

.. _lm_conf_inheritance_of_default_values:

Inheritance Of Default Values
-----------------------------

Given that the **Launch Manager** supports multiple levels of default values, specific rules govern their inheritance and application. The inheritance order is straightforward:

1. If a configuration value is not explicitly specified at a specific location (e.g., within an individual component's definition, a **Run Target's** definition, or a root-level property like ``alive_supervision``), the **Launch Manager** will first attempt to use the corresponding value from the user-defined ``defaults`` section.
2. If the value is also not specified within the user-defined ``defaults`` section, then the **Launch Manager** will apply the S-CORE standard default value for that option.