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    Web Application Firewall:Intelligent load balancing

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    Web Application Firewall:Intelligent load balancing

    Last Updated:Jul 03, 2026

    Intelligent load balancing uses multi-node access technology to enable automatic scheduling and disaster recovery across multiple nodes and lines, ensuring high availability and faster access to your services.

    Use cases

    Intelligent load balancing achieves high reliability through automatic network and service disaster recovery while providing low-latency access. It is ideal for the following scenarios:

    • Active geo-redundancy services: Multi-node services are deployed in the cloud or in data centers across multiple regions. All nodes are active simultaneously to provide services and serve as backups for disaster recovery. These services require high reliability and low-latency access.

    • Co-location multi-active services: Multi-node services are deployed in the cloud or in data centers within the same region. All nodes are active simultaneously to provide services and serve as backups for disaster recovery. These services require high reliability.

    • Co-location single-active services: A single-node service is deployed in the cloud or in a data center within the same region. This service is always online and requires high reliability.

      Note

      By default, co-location single-active services do not support automatic disaster recovery. However, you can use intelligent load balancing to achieve high reliability through automatic network disaster recovery.

    How it works

    After you enable intelligent load balancing, your WAF instance is assigned at least three protection nodes in different regions to provide automatic, multi-node disaster recovery. The feature uses intelligent DNS resolution and a Least-time back-to-origin algorithm to ensure the lowest latency for traffic from the protection node to your origin server.

    Note

    • After you enable intelligent load balancing for a WAF instance in the Chinese mainland, a protection node is assigned in each of the following regions for disaster recovery: China (Beijing), China (Hangzhou), and China (Shenzhen).

    • After you enable intelligent load balancing for a WAF instance outside the Chinese mainland, multiple protection nodes are assigned in major geographical areas, such as North America, Europe, and Southeast Asia, to provide disaster recovery.

    The following table compares WAF capabilities with and without intelligent load balancing.

    Feature

    Disabled

    Enabled

    Disaster recovery

    • Access protection based on multiple single-active nodes

    • Centralized failover

    • Access protection based on multi-node load balancing

    • Automatic network failover based on intelligent DNS resolution

    Access acceleration

    Not available

    Optimizes the shortest path by using nearest-node access and back-to-origin routing.
    image

    Benefits

    The following table describes the benefits of intelligent load balancing for each use case.

    Use case

    Benefit

    Diagram

    Active geo-redundancy services

    • Provides robust, automatic multi-line disaster recovery.

    • Distributed health checks enable multi-line load balancing.

    • The enhanced Least-time back-to-origin algorithm provides the lowest-latency path.

    		 image

    Co-location multi-active services

    • Provides robust, automatic multi-line disaster recovery.

    • Distributed health checks enable multi-line load balancing.

    		 image

    Co-location single-active services

    • Provides robust, automatic multi-line disaster recovery.

    • Distributed health checks enable multi-line load balancing.

    		 image

    Billing

    The intelligent load balancing feature is an add-on that you must purchase separately for your WAF instance.

    Pricing for the intelligent load balancing feature is based on the service duration of your WAF instance:

    • Instances in the Chinese mainland: USD 180/month

    • Instances outside the Chinese mainland: USD 800/month

    Procedure

    To use intelligent load balancing:

    1. Enable intelligent load balancing for your WAF instance.

      You can enable Intelligent Load Balancing when you purchase a WAF instance. You can also enable Intelligent Load Balancing for an existing instance by upgrading it. For more information, see Upgrade a WAF instance.

      Important

      For WAF instances in regions outside the Chinese mainland, intelligent load balancing is available only for the Business and Enterprise editions.

    2. Add your website to WAF in CNAME record mode. In the Enter Your Website Information step, add all your origin server addresses to the Origin Server Address field and select Least time as the Load Balancing Algorithm. Configure other settings as needed. For more information, see Add a domain name.

    3. Modify the DNS record for your domain name to point to the CNAME provided by WAF. This directs your website traffic through WAF for protection. For more information, see Modify a DNS record.

    After you complete these steps, your WAF instance automatically uses intelligent DNS resolution and the Least-time back-to-origin algorithm to process web requests, ensuring the lowest latency for traffic from the protection nodes to your origin servers.

    Important

    If you use an A record to map your new domain name to the WAF virtual IP address (VIP), your web services may become inaccessible when you enable or disable intelligent load balancing.