docs(medic/cht-core#10357): document LOG_LEVEL env variable for Docker deployments

content/en/hosting/cht/docker/logs.md

@@ -26,7 +26,46 @@ CHT has the following services running via Docker and each can have its logs que
 
 ## Setting log level
 
-By default, the CHT server logs are set to the `info` level. To change the log level to `debug`, you can set the `NODE_ENV` environment variable to `development`.  A log level of `debug` can affect system performance and cause log files sizes to grow rapidly.  It is recommended to temporarily set the log level to `debug` only when needed for troubleshooting.
+To control log verbosity, set the `LOG_LEVEL` environment variable for the `api` and `sentinel` containers. The default value is `info`.
+
+{{< callout type="info" >}}
+From version 5.1.0 onward, use `LOG_LEVEL` to control log verbosity. The `NODE_ENV` value no longer affects logging detail.
+{{< /callout >}}
+
+### Configuration
+
+Add `LOG_LEVEL` to the `.env` file used by your Docker Compose deployment:
+
+```
+LOG_LEVEL=debug
+```
+
+Then start or recreate the containers:
+```bash
+docker compose up -d
+```
+
+**Supported values:**
+
+- `error` — Only error messages
+- `warn` — Warnings and errors
+- `info` — General information (default, recommended for production)
+- `debug` — Detailed diagnostic information (troubleshooting only)
+
+{{< callout type="warning" >}}
+Using `debug` level generates significantly more logs and may impact performance. Use it only for troubleshooting and switch back to `info` or `warn` for normal operations.
+{{< /callout >}}
+
+### Applying changes to running containers
+
+To change the log level for already running containers, update the `LOG_LEVEL` value in your `.env` file and recreate the containers:
+```bash
+docker compose up -d
+```
+
+{{< callout type="info" >}}
+`docker compose restart` does not pick up environment variable changes. Use `docker compose up -d` to recreate the containers with the new configuration.
+{{< /callout >}}
 
 ## Viewing logs