HTTPDNS:Service IP address scheduling operation

Feature

You can call this operation to obtain the optimal and latest service scheduling information based on the source IP address and more disaster recovery capabilities. The following features are provided:

1. Queries a list of service IP addresses and allows clients to dynamically query the IP addresses of service nodes.

2. Lists a list of all domain names that are enabled. This way, clients can avoid invalid resolution requests.

3. Dynamically obtains the service endpoint list after a service node becomes abnormal.

Terms

Scheduling service: The operation that is used for scheduling. Service IP addresses and other service scheduling information are returned based on the source IP address.

Resolution service: The operation that is used for resolution. For more information, see the resolution service documentation.

Startup IP address: The IP address that is used to call the scheduling operation in the first startup or disaster recovery. This IP address does not provide resolution services.

Service IP address: The IP address that is used to call scheduling and resolution services.

Access method

1. Submit a ticket to apply for the startup IP address list.

   Note

   The startup IP address must be written in the app. To ensure service availability, multiple startup IP addresses are provided.

2. Use a startup IP address to call the scheduling service to obtain the list of service IP addresses.

   Note

   • The scheduling service supports HTTP and HTTPS access. For more information, see the Verify server identity section of this topic.

   • The startup IP address can be used only to call the scheduling service and does not provide the resolution service.

3. Use the service IP address to call the resolution service.

4. You must periodically use service IP addresses to call the scheduling service to Update the service IP address list and maintain the validity of the service IP address list.

   Note

   The service IP addresses provide both the scheduling service and the resolution service.

   • (Recommend) Update the service IP address list when a cold start is initiated

   • (Recommend) Update the service IP address list when you switch the network environment

   • (Recommend) Update the service IP address list at least once every 8 hours

5. When all service IP addresses are unavailable, use the startup IP address to call the scheduling service and obtain the list of available service IP addresses.

6. When all startup IP addresses are unavailable, use exponential backoff to retry updating the service IP address list.

   Important

   The service IP address list returned by the resolution service may expire. The service IP address list may change at any time.

Access method

URL: https://{Startup IP address_or_service IP address}/{account_id}/ss

Request method: GET

The following table describes the optional parameters used to troubleshoot scheduling exceptions.

The following table describes the optional parameters used to select nodes outside the Chinese mainland.

Verify the server identity:

• When you use the HTTPS request scheduling service, a valid certificate with the hostname 203.107.1.1 is provided regardless of which IP address is used. When you verify the server identity based on the certificate, ignore the hostname error in the certificate error and verify that the hostname in the certificate is 203.107.1.1.

• When you use the HTTP request scheduling service, the response content is signed based on the following parameters, and the signature value is placed in the X-Checksum-HmacMD field of the response header due to the lack of the TLS-based security mechanism.

Sample code:

• If the secretKey is IAmASecret, the random number n is 2EUenAaShVfy, and the current timestamp is 1568802250, the response content is {"service_ip": ["47.74.222.190"],"service_ipv6":["240b:4000:f10::178"]}

• Request URL: http://{Start IP address_or_service IP address}/{account_id}/ss?n=2EUenAaShVfy&t=1568802250

• sign = hmacMD5("IAmASecret", "2EUenAaShVfy-{"service_ip":["47.74.222.190"],"service_ipv6":["240b:4000:f10::178"]}-1568802250") = 3C74A498A00EEE6C5E7C599B3B882658

• The response header must contain X-Checksum-HmacMD5:3C74A498A00EEE6C5E7C599B3B882658.

Sample response:

If a request is successful, the HTTP status code 200 is returned. The response is in the JSON format. Example:

{
  "service_ip": [
    "47.74.222.190"
  ],
  "service_ipv6": [
    "240b:4000:f10::178"
  ]
}

If a request fails, the HTTP status code 4xx or 5xx and an error code are returned. The response is in the JSON format.

{
  "code": "MissingArgument"
}

Error codes