added access token expiry and refresh token expiry (#4230)

* added access token expiry and refresh token expiry

Modified access-token-expiry (1440 minutes) and refresh-token-expiry (10080 minutes) in the flag section and added them to the General Configuration.

* updated sensu-docs

As per review comments updated docs

* Added the 16.13.1 release notes to the Sensu documentation and deleted the Tessen reference tab.

Added the 16.13.1 release notes to the Sensu documentation and deleted the Tessen reference tab.

Author: sadashiv-sumo

content/sensu-go/6.13/observability-pipeline/observe-schedule/backend.md

@@ -332,7 +332,7 @@ Usage:
   sensu-backend start [flags]
 
 General Flags:
-      --access-token-expiry                       Control expiry of access token
+      --access-token-expiry                       Control expiry of access token (The duration must be specified in minutes, e.g.,access-token-expiry: 1440m)
       --agent-auth-cert-file string               TLS certificate in PEM format for agent certificate authentication
       --agent-auth-crl-urls strings               URLs of CRLs for agent certificate authentication
       --agent-auth-key-file string                TLS certificate key in PEM format for agent certificate authentication
@@ -386,7 +386,7 @@ General Flags:
       --pipelined-workers int                     number of workers spawned for handling events through the event pipeline (default 100)
       --platform-metrics-log-file string          platform metrics log file path
       --platform-metrics-logging-interval string  platform metrics logging interval
-      --refresh-token-expiry                      Control expiry of refresh token
+      --refresh-token-expiry                      Control expiry of refresh token (The duration must be specified in minutes, e.g., refresh-token-expiry: 10080m)
       --require-fips                              indicates whether fips support should be required in openssl  
       --trusted-ca-file string                    TLS CA certificate bundle in PEM format
 
@@ -446,6 +446,20 @@ annotations:
   sensu.io/plugins/slack/config/webhook-url: "https://hooks.slack.com/services/T00000000/B00000000/XXXXXXXXXXXXXXXXXXXXXXXX"
 {{< /code >}}
 
+| access-token-expiry | |
+|---------------------|-----|
+| description | Control expiry of access token. The duration must be specified in minutes. |
+| type | String |
+| default | 1440m |
+| environment variable | SENSU_BACKEND_ACCESS_TOKEN_EXPIRY |
+| command line example | {{< code shell >}}  
+sensu-backend start --access-token-expiry 1440m  
+{{< /code >}} |
+| backend.yml config file example | {{< code shell >}}  
+access-token-expiry: 1440m  
+{{< /code >}} |
+
+
 | api-listen-address  |      |
 -------------|------
 description  | Address the API daemon will listen for requests on.
@@ -670,6 +684,19 @@ metrics-refresh-interval: 10s{{< /code >}}
 
 <a id="state-dir-option"></a>
 
+| refresh-token-expiry | |
+|----------------------|-----|
+| description | Control expiry of refresh token. The duration must be specified in minutes. |
+| type | String |
+| default | 10080m |
+| environment variable | SENSU_BACKEND_REFRESH_TOKEN_EXPIRY |
+| command line example | {{< code shell >}}  
+sensu-backend start --refresh-token-expiry 10080m  
+{{< /code >}} |
+| backend.yml config file example | {{< code shell >}}  
+refresh-token-expiry: 10080m  
+{{< /code >}} |
+
 | state-dir  |      |
 -------------|------
 description  | Path to Sensu state storage: `/var/lib/sensu/sensu-backend`.

content/sensu-go/6.13/operations/monitor-sensu/tessen.md

@@ -9,6 +9,7 @@ version: "6.13"
 menu: "sensu-go-6.13"
 ---
 
+- [6.13.1 release notes](#6130-release-notes)
 - [6.13.0 release notes](#6130-release-notes)
 - [6.12.0 release notes](#6120-release-notes)
 - [6.11.0 release notes](#6110-release-notes)
@@ -118,6 +119,33 @@ Read the [upgrade guide][1] for information about upgrading to the latest versio
 
 ---
 
+## 6.13.1 — October 29, 2025
+The latest release of Sensu Go, version 6.13.1, is now available for download.  
+Read the [upgrade guide][1] to upgrade Sensu to version 6.13.1.
+
+### New Features
+- Added `access-token-expiry` backend configuration variable to control expiry of access tokens.  
+  *(The duration must be specified in minutes, e.g., `access-token-expiry: 1440m`)*
+- Added `refresh-token-expiry` backend configuration variable to control expiry of refresh tokens.  
+  *(The duration must be specified in minutes, e.g., `refresh-token-expiry: 10080m`)*
+
+### Improvements
+- Introduced fine-grained token expiry control via new backend configuration options.
+- Enhanced backend configurability to support environments requiring custom session lifetimes.
+
+### Fixes
+- Minor improvements and optimizations applied to backend configuration handling.
+- **Silence Creation Issues**: Fixed a bug where users were unable to create silences via the `curl` command when `max-silenced-expiry-time-allowed` and `default-silenced-expiry-time` flags were not set in `backend.yml`. These flags are now optional, allowing silences to be created via Web UI, `sensuctl`, and API without requiring these fields.
+- **UID Mapping Issues in Docker (RedHat and Alpine)**: Resolved a compatibility issue where Sensu Docker containers failed to run on systems using cgroupsv2, due to a file (`etcdctl`) having a UID exceeding the 65535 limit. All UIDs are now within the allowed range to support UID remapping and avoid container runtime errors.
+- **OIDC Integration Improvements for Microsoft Entra ID**: Resolved an issue where users were prompted for approval on every login when using Microsoft Entra ID as the OIDC provider. The login experience is now smoother, with Entra ID respecting previously granted permissions and reducing unnecessary approval prompts.
+
+### Removals
+- **Removed Tessen Telemetry Service**:  
+  The Tessen functionality has been removed from Sensu Go. Tessen previously collected and transmitted anonymized usage data to Sensu for product insights. Since the backend infrastructure supporting telemetry collection is no longer available, Tessen has been fully deprecated and removed from this release.  
+  Documentation related to Tessen has been updated or removed accordingly.
+
+---
+
 ## 6.13.0 release notes
 
 **April 10, 2025** — The latest release of Sensu Go, version 6.13.0, is now available for download.