Central Configuration System

The Central Configuration System in tlBMC provides a unified, structured mechanism to enable, disable, and parameterize various collectors and submodules. By loading a unified configuration bundle, tlBMC allows platforms to share a baseline configuration while overriding specific features for custom hardware.

The core config definitions reside in third_party/milotic/external/cc/tlbmc/central_config/.

Configuration Loading and Platform Selection

At boot, the central configuration manager loads the configuration:

Platform Detection: Reads the target platform machine name (e.g., by checking GBMC_TARGET_MACHINE inside /etc/os-release or similar OS configurations).
Configuration Bundle: Parses the configuration bundle protobuf textproto (usually located at /etc/tlbmc/tlbmc_config_bundle.textproto).
Config Selection:
- The bundle contains a general_config (type TlbmcConfig) and a map platform_to_config (mapping platform names to TlbmcConfig overrides).
- If the detected platform matches a key in platform_to_config, that platform-specific configuration merges with and overrides the general_config.
- If no match is found, the baseline general_config is used.
Static Registry: The merged configuration is registered as a static singleton accessible via GetTlbmcConfig().

Central Configuration Parameters

The configuration structures are defined in central_config.proto. The table below details all modules inside TlbmcConfig and their configuration options.

1. FRU Collector Module (`FruCollectorModule`)

Field	Type	Default	Description
`enabled`	`bool`	`false`	Enables/disables the FRU Collector.
`allow_dangling_frus`	`bool`	`false`	If `true`, permits loading FRUs without configs, and tolerates missing root chassis or invalid topology errors (testing only).
`own_cables_in_redfish`	`bool`	`true`	If `true`, tlBMC takes ownership of Redfish Cable resources.
`enable_deterministic_bmc`	`bool`	`false`	If `true`, enables deterministic hardware checks.
`own_assemblies_in_redfish`	`bool`	`false`	If `true`, tlBMC takes ownership of Redfish Assembly resources.
`own_chassis_in_redfish`	`bool`	`true`	If `true`, tlBMC takes ownership of individual Redfish Chassis URLs.
`no_associations_based_topology`	`bool`	`false`	If `true`, disables deriving topology context from DBus associations.
`own_chassis_collection_in_redfish`	`bool`	`true`	If `true`, tlBMC owns the Redfish Chassis Collection resource.
`strict_part_info_check`	`bool`	`false`	If `true`, verifies serial and part numbers to determine presence.
`expose_systems_child_links_in_chassis`	`bool`	`false`	If `true`, exposes Systems child links in Chassis resources.
`own_cable_collection_in_redfish`	`bool`	`false`	If `true`, tlBMC takes ownership of Redfish Cable Collection resource.
`expose_default_system_link`	`bool`	`true`	If `true`, expose default system link “system” in Redfish chassis and system urls when no system ID is configured.

2. Sensor Collector Module (`SensorCollectorModule`)

Field	Type	Default	Description
`enabled`	`bool`	`false`	Enables/disables the Sensor Collector.
`allow_sensor_creation_failure`	`bool`	`false`	If `true`, sensor creation errors will not abort startup (testing only).
`thermal_control_sub_module`	`ThermalControlSubmodule`	-	Submodule to control Fans, ThermalSubsystem, and PowerSubsystem.
`enable_threshold_monitoring`	`bool`	`false`	If `true`, periodically monitors thresholds and logs events.
`sensor_collection_append_sub_module`	`SensorCollectionAppendSubmodule`	-	Appends tlBMC sensors to the collection owned by gBMCWeb.
`drop_failed_duplicate_sensors`	`bool`	`false`	If `true`, a sensor that failed creation is dropped at startup when a successfully created sensor with the same key exists. For platforms that configure one physical device under every board it could belong to because the board cannot be identified.
`own_sensor_collection_in_redfish`	`bool`	`false`	If `true`, tlBMC will own the sensor collection in Redfish.

ThermalControlSubmodule Options

enabled (bool, default: false): Enables thermal/power subsystem ownership (controlling Fans, PowerSupplies, and Fan Mode actions).

SensorCollectionAppendSubmodule Options

enabled (bool, default: false): Enables append mode.
per_sensor_append_mode (bool, default: false): Appends individual sensors based on EM configuration.

3. Metric Collector Module (`MetricCollectorModule`)

Field	Type	Default	Description
`enabled`	`bool`	`true`	Enables/disables
: : : : software :
: : : : metrics. :
`collect_true_hitless_metrics`	`bool`	`true`	Collects hitless
: : : : metrics :
: : : : telemetry. :
`enable_psi_metrics`	`bool`	`false`	Collects host
: : : : Pressure Stall :
: : : : Information :
: : : : (PSI). :
`enable_bios_key_metrics`	`bool`	`false`	Controls the
: : : : BIOS Key metrics :
: : : : collector :
: : : : module. :

4. Install Module (`InstallModule`)

Field	Type	Default	Description
`enabled`	`bool`	`false`	Enables the firmware install service
: : : : (UpdateService and TaskService). :

5. Redfish Rate Limiter Module (`RedfishRateLimiterModule`)

Field	Type	Default	Description
`enabled`	`bool`	`false`	Registers the
: : : : rate limiter :
: : : : service at :
: : : : startup. :
`active`	`bool`	`false`	Actively
: : : : enforces rate :
: : : : limits on :
: : : : Redfish :
: : : : routes. :
`leak_rate_per_sec`	`double`	`100.0`	Token bucket
: : : : fill rate :
: : : : (sustained :
: : : : requests/sec). :
`bucket_capacity`	`double`	`200.0`	Token bucket
: : : : max capacity :
: : : : (max burst :
: : : : size). :
`bypass_uri`	`repeated string`	-	List of
: : : : Redfish URIs :
: : : : that bypass :
: : : : rate limiting. :
`red`	`RedfishRateLimiterRed`	-	Configures
: : : : Random Early :
: : : : Detection drop :
: : : : parameters. :

6. GPIO Collector Module (`GpioCollectorModule`)

Field	Type	Default	Description
`enabled`	`bool`	`false`	Enables discrete GPIO polling and the GpioCollector.
`power_control_sub_module`	`PowerControlSubmodule`	-	Submodule to handle host power control (GPIO or file-based).

PowerControlSubmodule Options

enabled (bool, default: false): Enables host power control.
power_control_type (PowerControlType, default: POWER_CONTROL_TYPE_GPIO): Specifies the mechanism for power control.

PowerControlType Options

POWER_CONTROL_TYPE_UNSPECIFIED: Unspecified.
POWER_CONTROL_TYPE_GPIO: Power control based on GPIO signals.
POWER_CONTROL_TYPE_FILE_BASED: Power control based on host state file.

7. Trust Bundle Install Module (`TrustBundleInstallModule`)

Field	Type	Default	Description
`enabled`	`bool`	`false`	Enables trust bundle
: : : : installation. If :
: : : : enabled, tlBMC owns :
: : : : `CertificateService` :
: : : : and restricts :
: : : : recovery :
: : : : authorization :
: : : : policy. :

8. Power Fault Log Collector Module (`PowerFaultLogCollectorModule`)

Field	Type	Default	Description
`enabled`	`bool`	`false`	Enables the Power Fault Log collector to
: : : : monitor and dump logs. :

9. SEL Collector Module (`SelCollectorModule`)

Field	Type	Default	Description
`enabled`	`bool`	`false`	Enables System Event Log (SEL) collection and
: : : : persistence. :

10. PCIe Collector Module (`PcieCollectorModule`)

Field	Type	Default	Description
`enabled`	`bool`	`false`	Enables the PCIe
: : : : collector module. :
: : : : Requires :
: : : : `GpioCollectorModule` :
: : : : to be enabled. :
`enable_collection_append_mode`	`bool`	`false`	If `true`, tlBMC
: : : : appends slots to :
: : : : gBMCWeb's PCIe slot :
: : : : collection. :
: : : : Otherwise, gBMCWeb :
: : : : owns the collection. :

11. TPU Debug Module (`TpuDebugModule`)

Field	Type	Default	Description
`enabled`	`bool`	`false`	Enables the TPU debug module.

12. Global Parameters

Field	Type	Default	Description
`platform_name`	`string`	-	Name of the platform.
`use_tlbmc_lite_config`	`bool`	`false`	If `true`, this platform uses
: : : : the TLBMC Lite configuration :
: : : : as a base. :

Configuration Example (`tlbmc_config_bundle.textproto`)

The following textproto shows a configuration bundle defining a default baseline and overriding values for the "platform1" platform.

general_config {
  platform_name: "default"
  fru_collector_module {
    enabled: true
    own_cables_in_redfish: true
    own_chassis_in_redfish: true
  }
  sensor_collector_module {
    enabled: true
    enable_threshold_monitoring: true
    sensor_collection_append_sub_module {
      enabled: true
      per_sensor_append_mode: true
    }
  }
  metric_collector_module {
    enabled: true
  }
}

platform_to_config {
  key: "platform1"
  value {
    fru_collector_module {
      enabled: true
      own_assemblies_in_redfish: true
    }
    sensor_collector_module {
      enabled: true
      thermal_control_sub_module {
        enabled: true
      }
    }
  }
}

Code References

Config Protos

central_config.proto

Central Configuration System

Configuration Loading and Platform Selection

Central Configuration Parameters

1. FRU Collector Module (FruCollectorModule)

2. Sensor Collector Module (SensorCollectorModule)

ThermalControlSubmodule Options

SensorCollectionAppendSubmodule Options

3. Metric Collector Module (MetricCollectorModule)

4. Install Module (InstallModule)

5. Redfish Rate Limiter Module (RedfishRateLimiterModule)

6. GPIO Collector Module (GpioCollectorModule)