docs: import ALB (#5454)

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site/content/blogs/release-v132.en.md

@@ -40,9 +40,10 @@ The `--watch` flag watches your workspace and rebuilds your containers when you
 
 ## Imported ALBs
 
-Copilot now introduces a new field `http.alb` in the [Load-Balanced Web Service manifest](../docs/manifest/lb-web-service.en.md). Rather than letting Copilot create a new Application Load Balancer in your environment to be shared among all load-balanced services, you may designate an existing public-facing ALB for a specific Load-Balanced Web Service (LBWS). Specify the ARN or name of an ALB from your VPC in your LBWS manifest:
+Copilot now supports the new field `http.alb` in the [Load-Balanced Web Service manifest](../docs/manifest/lb-web-service.en.md). Rather than letting Copilot create a new Application Load Balancer in your environment to be shared among all load-balanced services, you may designate an existing public-facing ALB for a specific Load-Balanced Web Service (LBWS). Specify the ARN or name of an ALB from your VPC in your LBWS manifest:
 
 ```yaml
 http:
   alb: [name or ARN]
 ```
+For imported ALBs, Copilot does not manage DNS-related resources like certificates.  

site/content/docs/concepts/environments.en.md

@@ -46,6 +46,13 @@ Optionally, when you set up an application, you can provide a domain name that y
 
 An internal ALB is created when a Backend Service with [`http`](../manifest/backend-service.en.md#http) configured in its manifest is deployed in an environment. For an HTTPS endpoint, use the [`--import-cert-arns`](../commands/env-init.en.md#what-are-the-flags) flag when running `copilot env init` and import a VPC with only private subnets. For more on internal ALBs, go [here](../developing/internal-albs.en.md).
 
+If you already have a public-facing ALB in your VPC and would like to use it instead of letting Copilot create one, specify that ALB by name or ARN in your Load-Balanced Web Service's manifest before deploying it to the environment:
+```yaml
+http:
+  alb: [name or ARN]
+```
+Your imported ALB will be associated with only that service (and any others that similarly import it), rather than shared among all load-balanced services in the environment.  
+
 ## Customize your Environment
 You can import your existing environment resources or configure the default ones by using flags with commands or by changing your [env manifest](../manifest/environment.en.md). If you want to customize more types of resources than are currently configurable, feel free to bring your use cases and cut an issue! 
 

site/content/docs/concepts/services.en.md

@@ -45,8 +45,8 @@ This option is suitable for HTTP or TCP services with steady request volumes tha
 require advanced configuration. 
 
 Note that a Copilot-managed Application Load Balancer is an environment-level resource, and is shared by all Load Balanced Web Services
-within the environment. To learn more, go [here](environments.en.md#load-balancers-and-dns). In contrast, a Network Load Balancer 
-is a service-level resource, and hence is not shared across services. As of v1.32.0, you have the option to import an existing ALB.
+within the environment. As of v1.32.0, you have the option to import an existing ALB at the service level by specifying it in your [workload manifest](../manifest/lb-web-service.en.md#http-alb). To learn more, go [here](environments.en.md#load-balancers-and-dns). In contrast, a Network Load Balancer 
+is a service-level resource, and hence is not shared across services.  
 
 Below is a diagram for a Load Balanced Web Service that involves an Application Load Balancer only.
 

site/content/docs/manifest/lb-web-service.en.md

@@ -283,8 +283,8 @@ at least one of Application Load Balancer or Network Load Balancer must be enabl
 <span class="parent-field">http.</span><a id="http-path" href="#http-path" class="field">`path`</a> <span class="type">String</span>  
 Requests to this path will be forwarded to your service. Each listener rule should listen on a unique path.
 
-<span class="parent-field">http.</span><a id="http-alb" href="#http-alb" class="field">`alb`</a> <span class="type">String</span>  
-The ARN or name of an existing public-facing ALB to import. Listener rules will be added to your listener(s).
+<span class="parent-field">http.</span><a id="http-alb" href="#http-alb" class="field">`alb`</a> <span class="type">String</span> <span class="version">Added in [v1.32.0](../../blogs/release-v132.en.md#imported-albs)</span>  
+The ARN or name of an existing public-facing ALB to import. Listener rules will be added to your listener(s). Copilot will not manage DNS-related resources like certificates. 
 
 {% include 'http-healthcheck.en.md' %}