This topic describes how to configure IP passthrough for passing client IP addresses to origin servers. This allows you to collect and analyze client IP addresses to meet your business requirements.

Background information

IP Application Accelerator (IPA) allows you to use the TCP Option Address (TOA) or PROXY protocol method to transfer client IP addresses to origin servers.
  • TOA: retrieves client IP address from the option section of a TCP header. To use this method, make sure that the origin server has the TOA kernel module installed. No modifications are required for your application.
  • PROXY protocol: retrieves client IP addresses from the PROXY protocol header. By default, all open source versions of NGINX accept the PROXY protocol header. You must configure other web servers to accept the PROXY protocol header.


  1. Log on to the DCDN console.
  2. In the left-side navigation pane, click IP Application Accelerator.
  3. On the IP Application Accelerator page, find the domain name that you want to manage and click Modify.
  4. In the left-side navigation pane of the specified domain name, click IP Application Accelerator.
  5. Click Modify.
  6. Select a method for Protocol Type.
    IP passthrough
  7. Click OK.
    After you configure IP passthrough, Dynamic Route for CDN (DCDN) provides better user experience.