After successfully installing DX OI, it is possible to login to the masteradmin tenant and create a new tenant.
After log out and trying to log back in with this new tenant, it redirects to http://adminui.<defaultSubDomain>/cloudmanagement which gives an HTTP Error 404.
In this specific case, DOI 1.3.2 and DX OI 20.2 were deployed in the same OpenShift cluster.
There are some routes that are re-used in both product versions which is causing problems as duplicate routes are not allowed.
For example: dxc, adminui, es and kibana
Release : 20.2
Component : CA DOI AO PLATFORM COMPONENTS
Apart from not running both product versions concurrently, separate routers could be added to the cluster to allow the different routes in each product version.
This is not an endorsement of this configuration, just an explanation of possible causes for failure.