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    Alibaba Cloud DNS:Health check

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    Alibaba Cloud DNS:Health check

    Last Updated:Jun 20, 2026

    When a server fails, standard DNS resolution continues to direct traffic to the failed address, causing service interruptions. The Health Check feature uses Global Traffic Manager 3.0 to continuously monitor the health of your backend servers. If a problem is detected, traffic is automatically rerouted to a healthy server, ensuring high availability and automatic failover.

    Important

    The Health Check for a DNS record is provided by the Global Traffic Manager 3.0 service. After you create an Access Domain, the system uses the Access Domain for DNS resolution and intelligent routing. This pay-as-you-go service enables more stable and efficient traffic management. Before you proceed, review the following changes:

    • Resolution service changes: The system prioritizes Global Traffic Manager 3.0 policies for intelligent routing and resolution, overriding DNS records in the Public Zone. After you disable or delete an Access Domain, the domain automatically reverts to the Public Zone for standard DNS resolution.

    • Billing: For information about the fees related to Global Traffic Manager 3.0, see Pricing.

    • Configuration changes: After you enable this feature, you must manage IP addresses (including adding, deleting, or modifying them) in the Global Traffic Manager 3.0 within the Global Traffic Manager 3.0 console, not through the DNS records in the Public Zone.

    • How to disable: To disable the Health Check feature, go to the Global Traffic Manager 3.0 console and disable or delete the corresponding Access Domain. The original DNS records in the Public Zone will then become active again.

    Prerequisites

    Before you use this feature, ensure you meet the following prerequisites:

    • Supported record types: You can enable Health Check only for the following record types: A, AAAA, and CNAME.

    • Protocol: Currently, the feature uses only the ICMP (PING) protocol to probe a record's connectivity. This means:

      • Your servers or network devices must allow ICMP requests. If a firewall blocks the ICMP protocol, the Health Check will always fail.

      • The default setup uses ICMP probing. For more granular Health Checks, such as port or application-layer probing, you can configure probe templates after creating the Access Domain.

    EnableHealth Check

    1. Log on to the Alibaba Cloud DNS - Public Zone console, find the target domain, and navigate to its details page.

    2. Go to the Settings tab. The Health Check option appears in the Actions column for A, AAAA, and CNAME records.

    3. In the Actions column of the target DNS record, click Health Check. In the dialog box that appears, configure the following options:

      • Interval: 15 Seconds, 1 Minute, 5min, 15min, 30min, or 60min.

      • Record Value Check: An Access Domain is generated based on the record set. All resolution lines for the same hostname and record type share a single Access Domain. You can enable or disable this feature for each line as needed.

      • Once enabled, the system uses the ICMP (PING) protocol to perform health checks on the record value, and the pay-as-you-go Global Traffic Manager service handles resolution. In the Health Check dialog box, select the Enable Health Check checkbox for the desired lines, and then click OK.

    4. Submit the form. The system creates the specified Access Domain and begins performing ICMP (PING) Health Checks on the record value. Resolution is now handled by Global Traffic Manager 3.0.

    5. After the configuration is complete, a GTM tag appears next to the record's Hostname.

      Important

      Resolution service changes: The system prioritizes Global Traffic Manager 3.0 policies for intelligent routing and resolution, overriding DNS records in the Public Zone. After you disable or delete an Access Domain, the domain automatically reverts to the Public Zone for standard DNS resolution.

    Pricing

    The Health Check feature uses Global Traffic Manager 3.0 and is billed on a pay-as-you-go basis. The fees consist of the following four billable items. For more information, see Pricing.

    Billable item

    Price

    Description

    Domain Name Count

    USD 0.015/domain name/day

    Billed by the number of Access Domain (including enabled and disabled ones). Settled daily.

    DNS Query Count

    USD 0.004/10,000 requests

    Billed by the number of DNS queries processed by GTM. Settled daily.

    Health Probe Count

    USD 1.5/10,000 checks

    Billed by the number of health checks performed on your addresses. Settled daily.

    Important

    If you disable an Access Domain, health check tasks for its addresses continue to run. To stop billing, delete the health check tasks.

    SMS Alerts

    USD 0.225/message

    Billed by the number of text message alerts sent. Settled daily.

    Cost estimation example

    Assume one Access Domain, 2 IP addresses, and 3 detection nodes. The nodes perform HTTP detection on 2 ports (such as 80 and 3000) for each IP address once per minute, with an average of 100,000 DNS requests and 1 text message alert per day.

    Estimated monthly cost:

    • Access domain name fee: 1 domain name × USD 0.015/domain name/day × 30 days/month = USD 0.45/month

    • Health check fee: 2 IP addresses × 2 ports × 3 detection nodes × 1 check/minute × 60 minutes/hour × 24 hours/day × 30 days/month × USD 0.00015/check = USD 77.64/month

    • GTM DNS resolution request fee: 100,000 requests/day × 30 days/month × USD 0.004/10,000 requests = USD 1.2/month

    • Text message alert fee: 1 message/day × 30 days/month × USD 0.225/message = USD 6.75/month

    • Total fee: 0.45 + 77.64 + 1.2 + 6.75 = USD 86.04/month

    Other operations

    Modify a DNS record

    Once Health Check is enabled for a DNS record, you can adjust the Access Domain or individual addresses for the Access Domain in Global Traffic Manager. For more information, see Configure an address pool and Configure an address. If you only want to modify the record value in the Public Zone to serve as a fallback when Health Check is disabled, follow these steps.

    1. Log on to the Alibaba Cloud DNS - Public Zone console, find the target domain, and go to its details page.

    2. Click the Settings tab, find the target DNS record, and click Edit in the Actions column.

    3. In the dialog box that appears, acknowledge the risk notification and click OK.

      A message will inform you that a Global Traffic Manager (GTM) instance is configured for the domain's A record. Consequently, all A record queries are routed based on GTM policies, and any modifications on the current page will not affect resolution. To restore standard resolution, disable or delete the corresponding GTM instance, or go to the Global Traffic Manager page to adjust the configuration.

    DisableHealth Check

    Important

    If you no longer need the Health Check feature, you can disable or delete the Access Domain. DNS resolution will then revert to using the Public Zone.

    1. Log on to the Alibaba Cloud DNS - Global Traffic Manager console.

    2. Click the switch to disable the Access Domain.

    3. If you no longer want to use Global Traffic Manager, click Delete in the Actions column.