[DOCS-9810] Add lambda section to HTTP Server source doc (#29222)

* add lambda section

* small edits and add links

* add anchor link from overview

* add recommendation

* Update content/en/observability_pipelines/sources/http_server.md

Co-authored-by: Brett Blue <[email protected]>

* Update content/en/observability_pipelines/sources/http_server.md

Co-authored-by: Brett Blue <[email protected]>

* apply suggestions

---------

Co-authored-by: Brett Blue <[email protected]>

Author: maycmlee

content/en/observability_pipelines/sources/http_server.md

@@ -5,6 +5,8 @@ disable_toc: false
 
 Use Observability Pipelines' HTTP/S Server source to collect HTTP client logs. Select and set up this source when you [set up a pipeline][1].
 
+You can also [send AWS vended logs with Datadog Lambda Forwarder to Observability Pipelines](#send-aws-vended-logs-with-the-datadog-lambda-forwarder-to-observability-pipelines).
+
 ## Prerequisites
 
 {{% observability_pipelines/prerequisites/http_server %}}
@@ -15,4 +17,40 @@ Select and set up this source when you [set up a pipeline][1]. The information b
 
 {{% observability_pipelines/source_settings/http_server %}}
 
-[1]: /observability_pipelines/set_up_pipelines/
+## Send AWS vended logs with the Datadog Lambda Forwarder to Observability Pipelines
+
+To send AWS vended logs to Observability Pipelines with the HTTP/S Server source:
+
+- [Set up a pipeline with the HTTP/S Server source](#set-up-a-pipeline).
+- [Deploy the Datadog Forwarder](#deploy-the-datadog-lambda-forwarder).
+
+**Note**: This is available for Worker versions 2.51 or later.
+
+### Set up a pipeline
+
+1. Navigate to [Observability Pipelines][1].
+1. Select the HTTP Server source:
+    1. Select **None** in the dropdown menu for **Authorization strategy**.
+    1. Select **JSON** in the dropdown menu for **Decoding**.
+1. After you set up your [destinations][2] and [processors][3], click **Next: Install**.
+1. On the **Install** page, enter the HTTP/S Server listener address, such as `0.0.0.0:9997`.
+1. Follow the rest of the instructions on the page to install the Worker based on your platform.
+
+### Deploy the Datadog Lambda Forwarder
+
+Follow the [Datadog Forwarder CloudFormation installation instructions][4] to deploy the Datadog Forwarder. After you have filled in `DdApiKey` and selected the appropriate `DdSite`, go to the **Log Forwarding (Optional)** section. Enter the following information in that section to set up the Forwarder to send logs to Observability Pipelines:
+
+1. In the **DdUrl** field, enter your load balancer address, which for this example is `9997`. **Note**: Datadog recommends fronting your Worker with a load balancer.
+1. In the **DdPort** field, enter `80`.
+1. If you want to encrypt traffic from the Datadog Forwarder to your Observability Pipelines Worker load balancer, you need to create an HTTPS listener and manage a certificate on your load balancer. Consult your cloud provider's documentation. For example in AWS, see [Create an HTTPS listener for your Application Load Balancer][5] for more information.
+1. If you do not need to maintain encryption between the Datadog Forwarder and load balancer, select **true** in the **DdNoSsl** dropdown menu.
+1. Click **Create stack**, and wait for the creation to complete.
+1. You can find the installed forwarder Lambda function under the stack's **Resources** tab with the logical ID `Forwarder`.
+1. [Set up triggers][6] for the installed Datadog Forwarder.
+
+[1]: https://app.datadoghq.com/observability-pipelines
+[2]: /observability_pipelines/destinations/
+[3]: /observability_pipelines/processors/
+[4]: /logs/guide/forwarder/?tab=cloudformation#installation
+[5]: https://docs.aws.amazon.com/elasticloadbalancing/latest/application/create-https-listener.html
+[6]: /logs/guide/send-aws-services-logs-with-the-datadog-lambda-function/?tab=awsconsole#set-up-triggers