問題

The following appears in web browsers:

The proxy server received an invalid response from an upstream server.
The proxy server could not handle the request GET /admin/dobackup.action.
Reason: Error reading from remote server

診断

Confluence is running behind Apache with Mod_Proxy configuration.

原因

• The proxy server received an invalid request from Tomcat utilized by Confluence.
• The web application did not respond in time and the request from Apache timed out.

ソリューション

Increase proxy timeout in Apache mod_proxy.