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    Alibaba Cloud DNS:GTM for cross-network access acceleration and failover

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    Alibaba Cloud DNS:GTM for cross-network access acceleration and failover

    Last Updated:Jun 02, 2026

    Overview

    Solution overview

    Enterprise applications that use IP addresses from multiple carriers often experience cross-network latency, packet loss, and outages. Global Traffic Manager (GTM) directs user requests to the nearest server based on the request source carrier, enabling nearest-point access, connection acceleration, and failover to minimize fault impact and ensure uninterrupted service.

    Target audience

    Enterprise network and O&M teams.

    Use cases

    1. Your application uses IP addresses from multiple carriers and experiences cross-carrier latency and packet loss.

    2. An IP address from a specific carrier becomes unavailable, making your service inaccessible to users from that carrier.

    Key concepts

    Term

    Description

    GTM

    Supports intelligent DNS resolution, health checks, fault isolation, and failover. Enables disaster recovery architectures such as dual-active intra-city or three-data-center, two-region setups.

    intelligent DNS resolution

    Routes users to the nearest server based on their carrier or region for low-latency access.

    health check

    Monitors servers from Layer 3 to Layer 7 to promptly detect application issues.

    primary and secondary address pools

    Groups service addresses from different data centers into primary and secondary pools for data center-level fault isolation and failover.

    Solution architecture

    Architecture diagram

    image

    Benefits

    • High availability: GTM monitors servers in real time and fails over traffic to other carriers automatically or manually. Fault detection to failover completion takes as little as one minute.

    • Access acceleration: Nearest-point access reduces latency for cross-carrier and cross-region traffic.

    • Simple integration: Complete configuration and traffic routing in as little as five minutes with no changes to existing services.

    • Simple O&M: As the first provider of this service in China, GTM enables unified management of IP addresses and traffic across data centers from different carriers, regions, and vendors.

    • Low cost: GTM costs as little as CNY 1,536 per year per domain with no additional IT investment. Traditional GSLB appliances cost hundreds of thousands of CNY, and custom disaster recovery systems require lengthy development.

    Implementation

    Prerequisites

    • Create a Global Traffic Manager instance.

      Note

      The Ultimate Edition completes failover in about one minute; the Standard Edition takes about three minutes. For high-availability requirements, use the Ultimate Edition.

    • Prepare the following resources: a China Unicom IP address 3.3.XX.XX, a China Telecom IP address 2.2.XX.XX, and a China Mobile IP address 1.1.XX.XX.

    Procedure

    1. Go to the Alibaba Cloud DNS - Global Traffic Manager console. In the instance list, find the target instance and click Configure in the Actions column.

    2. On the Address Pool Configuration page, create three address pools named "Mobile", "Telecom", and "Unicom" (address pool configuration). Enable Health Check for each address (health check).

      For each pool, set Load Balancing Policy to Return All Addresses, set the type to IPv4, and verify the health check status is Normal.

    3. Access policy configuration: On the Basic Configuration tab, select Geography-based Access Policy as the policy type, click Configure, and then click Add Access Policy to create four access policies. If a policy becomes abnormal, traffic falls back to the global policy.

    • Global access policy: Set Request Source to Global. For the primary address pool set, select the "Mobile", "Telecom", and "Unicom" pools. Leave the secondary address pool set empty.

    • China Telecom access policy: Set Request Source to China Telecom. For the primary address pool set, select the "Telecom" pool. Leave the secondary address pool set empty.

    • China Unicom access policy: Set Request Source to China Unicom. For the primary address pool set, select the "Unicom" pool. Leave the secondary address pool set empty.

    • China Mobile access policy: Set Request Source to China Mobile. For the primary address pool set, select the "Mobile" pool. Leave the secondary address pool set empty.

      After configuration, the policy list contains four entries: Unicom (China Unicom), Mobile (China Mobile), Telecom (China Telecom), and Global. Each uses IPv4 and can be managed with the Modify and Delete actions.

    1. Configure the Basic Configuration settings. Set the Global TTL to 1 min (adjustable based on your needs). Basic configuration.

      The Basic Configuration tab displays instance details including ID, name, edition, service domain name, CNAME access domain name, alert notification group, creation time, and expiration time. Click Modify to edit.

    2. Route live traffic: At your domain's DNS provider, add a CNAME record pointing your service domain name to the GTM CNAME access domain name.

    FAQ

    1. How long does failover take? With the Ultimate Edition (health check interval: 15s, TTL: 10s, consecutive failures: 2), GTM detects and fails over in about one minute. Changes propagate in approximately 10 seconds.

      With the Standard Edition (health check interval: 60s, TTL: 60s, consecutive failures: 2), failover takes about three minutes. Changes propagate in approximately 60 seconds.

      Important

      Propagation time depends on carrier local DNS cache duration. Some carriers extend caching to reduce recursive server load, which can increase global propagation time.

    2. Can I use GTM if my domain is not managed by Alibaba Cloud DNS? Yes. Add a CNAME record at your DNS provider pointing to the GTM CNAME access domain name.