This topic describes how to modify the information about an origin server in the Dynamic Route for CDN (DCDN) console.

Background information

DCDN supports the following origin types: OSS Domain, IP, and Site Domain. If you set the origin type to IP or Site Domain, you can specify one or more IP addresses or domain names as origin servers, and set the priority for each origin server.
Note Layer 4 health checks are performed on origin servers. Port 80, port 443, or custom ports of origin servers are probed. Probes are sent every 2.5 seconds. If an origin server fails three consecutive probes, the system marks the origin server as unavailable.

DCDN supports switchover between primary and secondary origin servers. If multiple origin servers are configured, DCDN preferentially redirects requests to the origin server whose Priority is Primary. If the primary origin server fails three consecutive health checks, Alibaba Cloud CDN redirects requests to the origin server whose Priority is Secondary. If the primary origin server passes the health check, the system marks the origin server as available and restores the priority of the origin server to primary. If you set the same priority for all origin servers, DCDN automatically redirects requests to origin servers in turn.

Procedure

  1. Log on to the DCDN console.
  2. In the left-side navigation pane, click Domain Names.
  3. On the Configure page, find the domain name that you want to manage and click Domain Names in the Actions column.
  4. On the Basic Settings tab, find the Origin Information section.
  5. In the Origin Information section, click Modify.
  6. In the Add Origin Server dialog box, set the following parameters.
    Origin settings
    Parameter Description
    Type
    • OSS Domain

      If you select OSS Domain, you can enter the public domain name of an Alibaba Cloud Object Storage Service (OSS) bucket in the Domain Name field. For example, you can enter xxx.oss-cn-hangzhou.aliyuncs.com. Internal endpoints of OSS buckets are not supported.

      You can view the public endpoint of an OSS bucket in the OSS console. You can also select an OSS bucket that belongs to the current Alibaba Cloud account from the Domain Name drop-down list.

    • IP

      If you select IP, you can enter the public IP address of the origin server in the IP field.

      Enter the public IP addresses of one or more servers. Public IP addresses of Alibaba Cloud Elastic Compute Service (ECS) instances do not need to be reviewed.

    • Site Domain
      If you select Site Domain, you can enter the domain name of your origin server in the Domain Name field.
      Note The origin domain name cannot be the same as the accelerated domain name. Otherwise, a DNS resolution loop occurs, and requests cannot be redirected to the origin server.
    Priority

    You can set priorities to specify primary and secondary origin servers. The primary origin server has a higher priority than secondary origin servers. DCDN preferentially redirects requests to the primary origin server.

    For example, if you set Origin Server A and B as the primary and secondary origin server, user requests are preferentially redirected to Origin Server A. If Origin Server A is down, user requests are redirected to Origin Server B until Origin Server A works as expected again.

    Weight

    If origin servers have the same priority, DCDN redirects requests to the origin servers based on their weights. This balances loads among the origin servers. Valid values of weights are 0 to 100. An origin server with a greater weight value receives a larger number of requests.

    For example, you have specified two origin servers: Server A and Server B, and both of them are primary origin servers. The weight of Server A is 80, and the weight of Server B is 20. In this case, DCDN redirects 80% of requests to Server A and 20% of requests to Server B.

    Port
    Select a port based on the protocol supported by the origin server.
    • Port 80: Requests are redirected to port 80 of the origin server.
    • Port 443: Requests are redirected to port 443 of the origin server. Make sure that the origin server supports HTTPS.
    Note Before you can specify a custom port, you must set Static Origin Protocol Policy and Dynamic Origin Protocol Policy to HTTP after you add a domain name. For more information, see Configure the static origin protocol policy and Configure back-to-origin requests to retrieve dynamic content.
  7. Click OK.