In OcNOS, dial-out telemetry subscriptions, also known as persistent subscriptions, ensure continuous data streaming, even if the Remote Procedure Call (gRPC) session terminates unexpectedly. With persistent subscriptions, the OcNOS device continuously retries to establish a gRPC connection to the collector server, thus maintaining persistent data streaming.

The dial-out telemetry feature in OcNOS comprises several key aspects ensuring seamless data streaming and connectivity with collector servers:

The described topology outlines a system architecture that utilizes gRPC-based tunneling for persistent streaming telemetry.

Here is a detailed explanation of the components and data flow:

The Data Flow: Dial-Out Mode flow chart illustrates streaming telemetry in Dial-out Mode.

Before configuring Dial-Out mode, ensure that:

Set up the OcNOS router to transmit streaming telemetry data to a gNMI client using the dial-out method.

The sample configuration on the OcNOS router sets up streaming telemetry subscriptions using gNMI to monitor specific paths related to the state of Hard Disk, RAM, and Chassis. The router sends telemetry data to the specified collector over a configured tunnel connection. The gNMI client subscribed to these paths will receive updates regarding the state of RAM and Hard Disk at the specified intervals. This setup enables proactive monitoring and management of key hardware components on the network device.

In this setup, an OcNOS router functions as the data source for streaming telemetry, while a gNMI client acts as the receiver of telemetry data. The OcNOS router sends telemetry data to the gNMI client over a dial-out connection.

To verify the telemetry configuration and view the overall commands used for dial-out subscriptions, use the show running-config streaming-telemetry command on the router.

To verify the telemetry configuration and view the overall commands used for dial-out subscriptions, use the show running-config streaming-telemetry command on the router.

To verify the telemetry configuration and view the overall commands used for dial-out subscriptions, use the show running-config streaming-telemetry command on the router.

To verify persistent telemetry configurations and monitor the telemetry data transmission settings on the router, check the output of the show streaming-telemetry persistent-subscriptions details command.

Start the gNMI collector with the --use-tunnel-server and publish options to receive the streamed gRPC responses. Execute the following command to start the gRPC tunnel server in listening mode, enabling it to accept incoming connections from gRPC tunnel clients (OcNOS target).

The following output represents telemetry data published by the gnmic command, monitoring the state of Hard Disk and RAM on the specified OcNOS router.

The output of the Publish RPC includes the following information:

The telemetry data output includes detailed fields for monitoring the state of the Hard Disk and RAM, offering insights into the memory and storage utilization of the OcNOS router.

Real-time Visibility: Operators have real-time visibility into network device health and performance metrics.

Proactive Maintenance: Early detection of issues allows for proactive maintenance and troubleshooting.

Optimized Resource Allocation: Insights from telemetry data help optimize resource allocation and capacity planning.

Enhanced Network Reliability: Continuous monitoring enhances network reliability and reduces downtime.

The streaming telemetry dial-out mode introduces the following configuration commands.

Use this command to create a destination-group for persistent subscriptions on the OcNOS device. The VRF parameter must match the VRF specified in the feature streaming-telemetry command. Can create and attach multiple destination-groups to activate streaming telemetry subscriptions.

Use the no form of this command to delete a destination-group.

None

Configure Mode

Introduced in OcNOS version 6.5.2.

The following example creates a destination group named tunnel-1 in a default VRF for transmitting telemetry data.

Use this command to add a destination-group under subscriptions. Can create multiple destination-groups within a subscription mode.

Use no parameter of this command to remove the destination-groups.

None

Telemetry-subscription Mode

Introduced in OcNOS version 6.5.2.

Ensure that the GRPC-GROUP-NAME (tunnel-1) is already configured in the current configuration mode.

The following commands illustrates how to add a destination group (tunnel-1) under subscription mode (sub-1) and verify the configuration using the show command output.

Use this command to specify or modify encoding types for subscriptions in streaming telemetry.

Use no parameter of this command to remove the encoding option.

None

Telemetry-subscription Mode

Introduced in OcNOS version 6.5.2.

The following commands demonstrate how to create a telemetry subscription named sub-3 using the JSON encoding type.

Use this command to set the interval for retry attempts when establishing a connection for the GNMI server to the tunnel-server. The VRF parameter must match the VRF specified in the feature streaming-telemetry command.

Use no parameter of this command to unset the retry-interval timer.

None

Configure mode

Introduced in the OcNOS version 6.5.2.

The following configuration illustrates how to set the retry-interval timer for the gNMI server to the tunnel-server with a value of 80 seconds in a default VRF.

Use this command to create a sensor group for persistent subscriptions in an OcNOS device. Multiple sensor groups can be created to specify the paths of interest for streaming telemetry. The VRF parameter must match the VRF specified in the feature streaming-telemetry command. These sensor groups are attached to subscriptions to activate streaming telemetry.

Use no parameter of this command to remove a created sensor group.

None

Configure mode

Introduced in OcNOS version 6.5.2.

The following commands demonstrate how to create a sensor group named stream-1 for persistent telemetry subscriptions in a default VRF on an OcNOS device:

Use this command to to associate a sensor group with a specific sampling interval under subscriptions for activating streaming telemetry. Multiple sensor groups can be created.

Use no parameter of this command to remove the sensor-groups from a subscription.

None

Telemetry-subscription Mode

Introduced in OcNOS version 6.5.2.

Ensure that the SENSOR-GROUP-NAME (stream-1) is already configured in the current configuration mode.

The following commands illustrates how to add a sensor group (stream-1) under subscription mode (sub-1) and verify the configuration using the show command output.

Use this command to add sensor paths under sensor-groups. Can add multiple sensor paths to a single sensor group.

Use no parameter of this command to remove sensor paths.

None

Telemetry-sensor-group Mode

Introduced in OcNOS version 6.5.2.

The following example demonstrates how to configure a sensor group (stream-1) and add multiple sensor paths to it for streaming telemetry.

Use this command to display a brief summary of the streaming-telemetry dial-out configurations. This command provides a concise view of the persistent subscription settings configured on the device.

None

Exec mode

Introduced in OcNOS version 6.5.2.

The command output lists each persistent subscription with its associated details.

The following table explains the output fields.

Use this command to create named subscriptions for persistent telemetry configurations in an OcNOS device. The VRF parameter must match the VRF specified in the feature streaming-telemetry command. Multiple subscriptions can be created. These subscriptions are essential for activating streaming telemetry, as they define specific settings such as associated destination groups and sensor groups.

Use no parameter of this command to delete a subscription.

None

Configure Mode

Introduced in OcNOS version 6.5.2.

The following command demonstrates configuring a subscription (sub-1) on an OcNOS device. The subscription remains in-active because the sensor groups and destination groups have not been added to it.

Use this command to add tunnel-servers under destination groups. Can create multiple tunnel servers within a destination group.

Use no parameter of this command to remove a tunnel server from the destination group.

None

Telemetry-GRPC-tunnel-group Mode

Introduced in OcNOS version 6.5.2.

The following command demonstrates how to add a tunnel server within the destination group.

The following is the revised command for telemetry.

The following provides definitions for key terms or abbreviations and their meanings used throughout this document: