Menu
DocumentationGrafana CloudTest applications and servicesSynthetic MonitoringCreate checksCheck typesTCP check
Grafana Cloud
TCP check
A TCP check connects to an endpoint on a given hostname or IP address and a port. This ensures a server accepts the connection and measures response latency and uptime.
Options
The list of common options to all check types:
Option | Description |
---|---|
Enabled | Whether the check is enabled or not. |
Job name | Refer to the check name. Check metrics include a job label with the value of this option. |
Target | Target of the check request. Check metrics include an instance label with the value of this option. |
Probe locations | The locations where the check should run from. Check metrics include a probe label with the value of the probe location running the check. |
Frequency | The frequency the check should run in seconds. The value can range from 60 to 3600 seconds. Only the sm_check_info metric includes the frequency label. |
Timeout | Maximum execution time for the check. The value can range from 1 to 60 seconds. |
Custom labels | (Optional) Custom labels applied to check metrics. Refer to Custom labels for querying instructions. |
Additionally, TCP checks have the following options:
Option | Description |
---|---|
Use TLS | Whether or not TLS is used when the connection is initiated. |
Query and response | The response to expect and the data to send. |
Disable target certificate validation | Whether to validate the certificate that is presented. |
Server name | The server name used during certificate validation. |
CA certificate | The certificate for the certificate authority. |
Client certificate | The client certificate to present during authentication. |
Client key | The corresponding key for the client certificate. |
IP version | The internet protocol version to use (V4, V6, or any). |
Publish full set of metrics | Whether to publish additional metrics to create histograms (used for Apdex scores or heatmaps). Default is false to reduce the number of active series. |
These last options don’t produce any additional labels in the resulting check metrics.
Metrics
Checks store their results as Prometheus metrics, including the list of common metrics:
Metric | Description |
---|---|
probe_all_duration_seconds | Returns how long the probe took to complete in seconds (histogram). |
probe_duration_seconds | Returns how long the probe took to complete in seconds. |
probe_all_success | Displays whether or not the probe was a success (summary). |
probe_success | Displays whether or not the probe was a success. |
sm_check_info | Provides information about a single check configuration. |
Additionally, TCP checks produce the following metrics:
Metric | Description |
---|---|
probe_dns_lookup_time_seconds | Returns the time taken for probe DNS lookup in seconds. |
probe_failed_due_to_regex | Indicates if probe failed due to regular expression. |
probe_ip_addr_hash | Specifies the hash of the IP address. It’s useful to detect if the IP address changes. |
probe_ip_protocol | Specifies whether the probe IP protocol is IP4 or IP6. |
probe_ssl_earliest_cert_expiry | Returns last SSL chain expiry in Unix time. |
probe_ssl_last_chain_expiry_timestamp_seconds | Returns last SSL chain expiry in timestamp. |
probe_ssl_last_chain_info | Contains SSL leaf certificate information. |
probe_tls_version_info | Returns the TLS version used or NaN when unknown. |
Was this page helpful?
Related resources from Grafana Labs
Additional helpful documentation, links, and articles:
Video
Getting started with the Grafana LGTM Stack
In this webinar, we’ll demo how to get started using the LGTM Stack: Loki for logs, Grafana for visualization, Tempo for traces, and Mimir for metrics.
Video
Intro to Kubernetes monitoring in Grafana Cloud
In this webinar you’ll learn how Grafana offers developers and SREs a simple and quick-to-value solution for monitoring their Kubernetes infrastructure.
Video
Building advanced Grafana dashboards
In this webinar, we’ll demo how to build and format Grafana dashboards.