The telemetry components in the Substrate outer node provide low-level information about the operation of the network. The information exposed can be sent to a backend telemetry server where it can be collected into a data series for display in a front-end dashboard or charts and graphs.

Substrate telemetry relies on the tracing library from the Tokio Rust crate to log and transmit information about node operations. The tokio tracing layer sends the information it collects through an asynchronous channel to a background task called TelemetryWorker. The TelemetryWorker forwards the information to one or more remote telemetry servers. You can use the --telemetry-url command-line option when you start a node to specify to specify the telemetry server that you want to send telemetry data to.

impl Telemetry source pub fn starttelemetry( &mut self, connectionmessage: ConnectionMessage ) -> Result<()> Initialize the telemetry with the endpoints provided in argument for the current substrate node.

This method must be called during the substrate node initialization.

The endpoints argument is a collection of telemetry WebSocket servers with a corresponding verbosity level.

The connection_message argument is a JSON object that is sent every time the connection (re-)establishes.

source pub fn handle(&self) -> TelemetryHandle Make a new cloneable handle to this Telemetry. This is used for reporting telemetries.


name: String Node’s name.

implementation: String Node’s implementation.

version: String Node’s version.

config: String Node’s configuration.

chain: String Node’s chain.

genesis_hash: String Node’s genesis hash.

authority: bool Node is an authority.

startup_time: String Node’s startup time.

network_id: String Node’s network ID.

target_os: String Node’s OS.

target_arch: String Node’s ISA.

target_env: String Node’s target platform ABI or libc.

sysinfo: Option Node’s software and hardware information.

The telemetry information includes details about the hardware and software running on the node, including:

  • The exact CPU model.
  • The total amount of memory, in bytes.
  • The number of physical CPU cores.
  • The Linux kernel version.
  • The exact Linux distribution used.
  • Whether the node’s running under a virtual machine.

If multiple Substrate nodes are running in the same process, the TelemetryWorker uses a tracing::Span trait to identify which Substrate node is reporting the data. Every task spawned using sc-service’s TaskManager automatically inherits this span.

By default, when you start a Substrate node, the node initializes a Telemetry data structure instance that can be used to send telemetry messages. The Telemetry instance connects to the remote endpoints the node should send data to and sets up a TelemetryWorker thread to run in the background. The TelemetryWorker registers a new TelemetryWorkerHandle to use for asynchronous communication ng with the running TelemetryWorker dedicated to registration. Registering can happen at any point in time during the process execution.

Metrics and dashboards

Block production Throughput Network activity and performance

Alerting on bad behavior