Overview of Logging and Metrics

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This topic provides an overview of logging and metrics in VMware Tanzu Application Service for VMs (TAS for VMs). It includes information about logs and metrics sources and transport systems. It also lists products for viewing logs and metrics.

Accessing Metrics

You must use a cf CLI plugin to access and view metrics directly from the command line. You can use either the Firehose plugin or the Log Cache plugin to access metrics through the cf CLI.

Log Cache CLI plugin

Use the Log Cache plugin with the cf CLI to access metrics.

  1. Log in to the cf CLI by running: cf login -a API-URL -u USERNAME -p PASSWORD

Where: * API-URL is your API endpoint. * USERNAME is your username. * PASSWORD is your password.

  1. Install the Log Cache CLI plugin. For more information, see cf CLI Plugins.

  2. Run the following command followed by the metric you want to see and any parameters. cf query 'METRIC-NAME{source_id="SOURCE-ID"}'


Where: * METRIC-NAME is the name of your metric. * SOURCE-ID is the ID of your source.

To find the source ID and metric name of Key Performance Indicators, see Key Performance Indicators. To find the source ID and metric name of Key Capacity Scaling Indactors, see Key Capacity Scaling Indicators.

cf Nozzle Command

Use the Firehose plugin cf nozzle command in the cf CLI to access metrics.

  1. Log in to the cf CLI by running: cf login -a API-URL -u USERNAME -p PASSWORD Where:
  2. API-URL is your API endpoint.
  3. USERNAME is your username.
  4. PASSWORD is your password.

  5. Install the Firehose cf CLI plugin. For more information, see cf ClI Plugins.

  6. Run the following command followed by the metric you want to see and any parameters. cf nozzle -no-filter | grep SOURCE-ID | grep -i METRIC-NAME

Where: * METRIC-NAME is the name of your metric. * SOURCE-ID is the ID of your source.

For example: cf nozzle -no-filter | grep bbs | grep -i ConvergenceLRPDuration

To find the source ID and metric name of Key Performance Indicators, see Key Performance Indicators. To find the source ID and metric name of Key Capacity Scaling Indactors, see Key Capacity Scaling Indicators.

Note: Run the `cf nozzle` command until you have recieved all expected metrics have been recieved.

For more information about nozzles, see Logs, Metrics, and Nozzles.

Sources of Logs and Metrics

There are two sources of TAS for VMs logs and metrics:

  • TAS for VMs platform components, such as a Diego Cell, MySQL Server, or Cloud Controller
  • Apps and app containers deployed on TAS for VMs

The table below describes the data included in logs and metrics from each source:

Source Logs Data Metrics Data
Platform components Logs from TAS for VMs components
  • Health metrics from BOSH-deployed VMs1
  • Platform metrics from TAS for VMs components. For example, Diego Cell capacity remaining and Gorouter throughput.
  • Metrics for any service tile that self-publishes to the Loggregator Firehose. For example, Redis and MySQL.
Apps and app containers Logs from apps2
  • Container metrics3
  • Custom app metrics4

1For more information about using the BOSH Health Monitor to collect health metrics on VMs, see Configuring a Monitoring System.

2For more information about app logging, see App Logging in TAS for VMs.

3For more information about container metrics, see Container Metrics.

4For more information about configuring an app to stream custom metrics to Loggregator, see Metric Registrar and Custom App Metrics.

Transport Systems for Logs and Metrics

The following transport systems deliver logs and metrics from their source to an observability product for viewing:

  • Loggregator: Loggregator is the transport system for both logs and metrics on apps deployed on TAS for VMs, as well as metrics on TAS for VMs platform components. For more information about the Loggregator system, including Loggregator architecture and components, see Overview of the Loggregator System.

  • rsyslogd on TAS for VMs component VMs: rsyslogd is the transport system for TAS for VMs component logs. Users can configure rsyslogd to transport component logs to a third-party syslog server.

The table below lists the transport system for logs and metrics on TAS for VMs platform components and apps:

Source Logs Transport System Metrics Transport System
Platform components rsyslogd on TAS for VMs component VMs Loggregator
Apps Loggregator Loggregator

Viewing Logs and Metrics

The table below lists the products and tools for viewing TAS for VMs logs and metrics:

Source Products and Tools for Viewing Logs Products and Tools for Viewing Metrics
Platform components To view system logs from TAS for VMs components, configure rsyslogd to transport logs to a third-party product. You can use the following products or tools to view platform component and VM metrics:
Apps You can use the following products or tools to view app logs: You can use the following products or tools to view app metrics: