--- title: "PDC agent metrics | Grafana Cloud documentation" description: "Learn about the Prometheus-compatible metrics exposed by the PDC agent, including how to scrape them and example PromQL queries." --- # PDC agent metrics The PDC agent exposes Prometheus-compatible metrics for monitoring and alerting. By default, you can access these metrics at `http://:8090/metrics`. You can change the metrics port using the [`-metrics-addr` flag](/docs/grafana-cloud/connect-externally-hosted/private-data-source-connect/pdc-agent-cli-reference/). You can also disable metric parsing from SSH logs with the [`-parse-metrics` flag](/docs/grafana-cloud/connect-externally-hosted/private-data-source-connect/pdc-agent-cli-reference/). > Note > > For Grafana Cloud-side PDC metrics such as connected agent count and request duration, refer to [View PDC activity in the `grafanacloud-usage` data source](/docs/grafana-cloud/connect-externally-hosted/private-data-source-connect/configure-pdc/#view-pdc-activity-in-the-grafanacloud-usage-data-source). ## Scrape the metrics To collect PDC agent metrics, configure a Prometheus-compatible scraper to target the agent’s metrics endpoint. The following example shows a [Grafana Alloy](/docs/grafana-cloud/send-data/alloy/) configuration: Alloy ![Copy code to clipboard](/media/images/icons/icon-copy-small-2.svg) Copy ```alloy prometheus.scrape "pdc_agent" { targets = [ {"__address__" = ":8090"}, ] forward_to = [prometheus.remote_write.default.receiver] } ``` Replace `` with the hostname or IP address of the machine running the PDC agent. If you changed the metrics port with `-metrics-addr`, update the port accordingly. ## Available metrics The metrics include counters, gauges, and native histograms that provide insight into the agent’s behavior, including: - SSH connection count and duration - TCP connection counts - Signing request latency - Restart counts with exit codes - Agent version information The PDC agent exposes the following metrics: Expand table | Metric name | Type | Description | Labels | |-----------------------------------------------|------------------|----------------------------------------------------|--------------------------------------| | `pdc_agent_agent_info` | Gauge | Set to `1` with labels identifying the agent build | `version`, `ssh_version`, `stack_id` | | `pdc_agent_signing_requests_duration_seconds` | Native histogram | Duration of signing requests in seconds | `status` | | `pdc_agent_ssh_connections` | Gauge | Number of open SSH connections | none | | `pdc_agent_ssh_restarts_total` | Counter | Total number of SSH restarts | `connection`, `exit_code` | | `pdc_agent_ssh_open_channels` | Gauge | Number of open SSH channels | `connection` | | `pdc_agent_tcp_connections_total` | Counter | Number of opened TCP connections | `connection`, `target`, `status` | | `pdc_agent_ssh_time_to_connect_seconds` | Native histogram | Time spent to establish SSH connection | `connection` | ### The `connection` label The `connection` label appears on several metrics and identifies which parallel SSH connection emitted the metric. It corresponds to the [`-connections` flag](/docs/grafana-cloud/connect-externally-hosted/private-data-source-connect/pdc-agent-cli-reference/). When running with the default single connection, the label value is `0`. If you increase `-connections` to 3, you see values `0`, `1`, and `2`. ## Use cases and example queries The following examples show how to use PDC agent metrics for monitoring, alerting, and troubleshooting. ### Confirm agent availability Use `pdc_agent_agent_info` to verify that a PDC agent is running and to identify its version: promql ![Copy code to clipboard](/media/images/icons/icon-copy-small-2.svg) Copy ```promql pdc_agent_agent_info ``` A result of `1` for each agent instance confirms it is up. The `version` and `ssh_version` labels help you verify that agents are running the expected software versions. ### Track SSH restart rate A high rate of SSH restarts can indicate network instability or server-side issues. Use the `exit_code` label to break down restarts by cause: promql ![Copy code to clipboard](/media/images/icons/icon-copy-small-2.svg) Copy ```promql sum by (exit_code) (rate(pdc_agent_ssh_restarts_total[5m])) ``` Refer to [PDC agent exit codes](/docs/grafana-cloud/connect-externally-hosted/private-data-source-connect/troubleshooting/#pdc-agent-exit-codes) for details on what each exit code means. ### Monitor open SSH channels A rising number of open channels can indicate that an agent is becoming overloaded. The [troubleshooting guide](/docs/grafana-cloud/connect-externally-hosted/private-data-source-connect/troubleshooting/#pdc-agent-overload-and-unresponsiveness) recommends monitoring CPU usage as the primary indicator, and open channels provides a complementary signal: promql ![Copy code to clipboard](/media/images/icons/icon-copy-small-2.svg) Copy ```promql pdc_agent_ssh_open_channels ``` ### Track TCP connection success and failure rates Use the `status` label to compare successful and failed TCP connections to your data source targets: promql ![Copy code to clipboard](/media/images/icons/icon-copy-small-2.svg) Copy ```promql sum by (target, status) (rate(pdc_agent_tcp_connections_total[5m])) ``` A high failure rate for a specific `target` suggests the data source is unreachable from the agent. Refer to the [troubleshooting guide](/docs/grafana-cloud/connect-externally-hosted/private-data-source-connect/troubleshooting/) for common causes. ### Measure signing request latency Track the p99 latency of certificate signing requests to detect API performance issues: promql ![Copy code to clipboard](/media/images/icons/icon-copy-small-2.svg) Copy ```promql histogram_quantile(0.99, rate(pdc_agent_signing_requests_duration_seconds[5m])) ``` ### Monitor SSH connection establishment time Track how long it takes the agent to establish an SSH connection to the PDC server. Elevated connection times can indicate network latency or congestion: promql ![Copy code to clipboard](/media/images/icons/icon-copy-small-2.svg) Copy ```promql histogram_quantile(0.99, rate(pdc_agent_ssh_time_to_connect_seconds[5m])) ```