Configure multiple HTTPS websites on a single ALB instance

Example scenario

An Application Load Balancer (ALB) instance uses the domain name from an incoming HTTPS request to find the matching certificate. After completing HTTPS authentication, it routes the request to the appropriate backend server based on the configured forwarding rules.

Prerequisites

• You have created an Application Load Balancer (ALB) instance. For more information, see Create and manage ALB instances.

• You have created two server groups: RS1 and RS2. For more information, see Create and manage server groups.

• You have added backend servers to the server groups: an ECS instance named ECS01 to RS1 and another named ECS02 to RS2. You have also deployed your applications on both ECS instances.

• You have registered your domain names and obtained Internet Content Provider (ICP) filings for them. For more information, see Register a domain name on Alibaba Cloud and ICP filing process.

• You have purchased or uploaded the necessary certificates to Certificate Management Service and associated them with their respective domain names. For more information about how to create a certificate, see Enable HTTPS for a website by using a commercial certificate. This topic requires the following certificates:

  • A default certificate named default associated with the domain name aliyundoc.com.

  • An additional certificate named example1 associated with the domain name www.example.com.

  • An additional certificate named example2 associated with the domain name www.example.org.

Step 1: Add an HTTPS listener

1. Log on to the Application Load Balancer console.

2. In the top navigation bar, select the region where the ALB instance is deployed.

3. In the left-side navigation pane, select Instances.

4. On the Instances page, find the target instance and click Create Listener in the Actions column.

5. On the Configure Listener page, configure the following parameters and keep the default values for other parameters. Then, click Next.

   Parameter	Description
   Listener Protocol	Select HTTPS.
   Listener Port	Set the port to 443.

6. On the Configure SSL Certificate page, configure the following parameter and keep the default values for other parameters. Then, click Next.

   Parameter	Description
   Server Certificate	Select the default certificate that you prepared, named default.

7. On the Select Server Group page, configure the following parameter and keep the default values for other parameters. Then, click Next.

   Parameter	Description
   Server Group	Select the server group RS1 that you created.

8. On the Configuration Review page, review your settings and click Submit.

Step 2: Add additional certificates

1. On the Instances page, find the target instance and click its ID.

2. Click the Listener tab. Find the HTTPS listener and click Manage Certificates in the Actions column.

3. Click the Certificates tab and then click Add EV Certificate.

4. In the Add Additional Certificate dialog box, select the certificate example1 and click OK. Repeat this step to add the additional certificate example2.

Step 3: Configure forwarding rules

1. On the Instances page, find the target instance and click its ID.

2. Click the Listener tab. Find the HTTPS listener and click View/Modify Forwarding Rule in the Actions column.

3. On the Forwarding Rules tab, click Add New Rule.

4. Configure the following two forwarding rules and click OK.

   • If the Domain Name is www.example.com, then Forward RS1. Set the Weight to 100.

   • If the Domain Name is www.example.org, then Forward RS2. Set the Weight to 100.

Step 4: Configure domain name resolution

Add CNAME records for www.example.com and www.example.org to point to the public DNS name of your ALB instance.

1. Log on to the Application Load Balancer console.

2. In the top navigation bar, select a region.

3. Find the target ALB instance and copy its Domain Name.

4. Follow these steps to add a CNAME record.

   Note

   If your domain names are not registered with Alibaba Cloud, you must first add them to the Alibaba Cloud DNS console before configuring DNS settings. For more information, see Domain management. If your domain name is registered with Alibaba Cloud, proceed with the following steps.

   1. Log on to the Alibaba Cloud DNS console.

   2. On the Public Zone page, find the target domain name and click Settings in the Actions column.

   3. On the Settings page, click Add Record.

   4. In the Add Record panel, configure the following parameters for the CNAME record, and then click OK.

      Parameter	Description
      Record Type	Select CNAME from the drop-down list.
      Hostname	The prefix of your domain name, such as www.
      Query Source	Keep the default value.
      Record Value	Enter the CNAME address for the domain name. This is the DNS name of the ALB instance that you copied.
      TTL	Specifies the duration that a DNS record is cached on a DNS server. Keep the default value.

      Note

      • New CNAME records take effect immediately. The propagation time for a modified CNAME record depends on the TTL of the cached record on the local DNS server. The default TTL is 10 minutes.

      • If a conflict occurs when you add the record, use a different hostname. For more information, see DNS record conflict rules.

Step 5: Verify the configuration

Related documents

For more information about forwarding rules, see Configure domain-based and path-based forwarding rules.