Gateway Logs

A timestamped series of log messages can provide insight into device operation. Time-series event logging is important for security and drive monitoring. The log processing feature in the Pelion Edge gateway stack supports log collection of various standard Linux log sources.

Log processing

FluentBit is a log processor, stream processor and forwarder for Linux and various other operating systems. Pelion Edge uses FluentBit to collect logs from various input plugins for its services, parse them and forward them to Pelion Device Management.

Configuration

The FluentBit daemon runs as a system service managed by systemd. The service parameters are defined in the systemd unit file or config file for the FluentBit service that contains the FluentBit log processing chain. The FluentBit daemon is configured through this standard configuration file. The config file holds information on the input plugins used to collect logs, how to parse them and where to forward the collected log stack.

Dynamic log settings or remote configuration

You can define your own processing chains to customize the data collected from a device to meet your particular needs. You can configure the processing chain at run time through a configuration file.

The Pelion Edge gateway advertises the features supported by the platform using Pelion's reserved FeatureMgmt LwM2M object 33457 with three resources:

• 0: featureID.
• 1: enabled.
• 2: config.

This provides an interface for discovering the gateway's feature capabilities and to manage the configuration of enabled features. Refer to the Maestro configuration documentation to learn more about the gateway capability discovery feature. The FluentBit logging feature is also one such Feature Management instance. FeatureMgmt config resource for the FluentBit service allows you to remotely view the current logging configuration and also push a config update using the Pelion Device Management service APIs. When such an update is triggered, the edge gateway can instantly apply the changed configuration.

Log service

Gateway Logs Service stores logs in one location, so you can discover and resolve issues when debugging. The gateway sends its logs to the service, which stores and filters them. You can then review the logs and sort them based on the filters Gateway Logs Service provides.

The supported filters are:

• Account ID.
• Device ID.
• Log ID.
• Application name.
• Log type.
• Log time stamp.
• Log severity level, such as debug, trace, info, warning, error and critical.

Prerequisites

To use Gateway Logs Service, you need an access key to access Pelion Edge gateway services.

Using the service

With Gateway Logs Service, you can:

• Add logs: using the gateway domain log endpoint(used as an http output plugin under the default fluent-bit config).
• List all logs: using the public Gateway Logs API endpoints.
• View logs based on appropriate filters.

Security considerations

• Gateway Logs Service only accepts HTTPS connections, which are secured by Secure Sockets Layer (SSL) protocol. It provides privacy and data integrity between two or more communicating applications.
• You can only talk to a gateway if you are part of the account tied to that gateway.
• For gateway domain requests, the gateway authenticaiton server has to confirm whether the request is from a valid gateway.
• All requests made to the API domain must pass through the API gateway, which ensures the request contains a valid access token. The Gateway Logs Service assumes the API gateway handles authentication for API domain requests.