Symptoms
Configuration import wizard fails by timeout.
Cause
Operation takes more time than specified in http proxy directive on OA UI node.
Resolution
To fix the issue it is necessary to set or adjust the http proxy timeout on all OA UI nodes.
More info about proxy timeout directive can be found in official apache documentation at:
https://httpd.apache.org/docs/current/mod/mod_proxy.html#proxytimeout
The directive is located in the following configuration file:
/etc/httpd/conf.d/ng_custom.conf