OE Explorer of release 12 is showing 11.7 resources

OE 12.x OpenEdge Explorer (OEE) / OpenEdge Management (OEM) shows local OpenEdge 11.7 managed resources such as databases, AppServers, etc.
OEM / OEE shows the local AdminServer as online, but when selecting a resource a message shows: Adminserver is offline.

The admserv.log file contains the following entry:

Adding remote AdminServer connection for fathom1.[hostname] to localhost:6835

The OpenEdge 11.7 AdminServer is running when starting version 12 OEE / OEM.

The version 12 OEE / OEM (fathom) will try to bind to the AdminServer through port 6835 by default, as all AdminServers including the local AdminServer are considered "Remote AdminServers" in this version.

Basic guide with steps to fix the issue:

1. Stop OE 11.7 OpenEdge Explorer/Management (OEE/OEM)
2. Stop OE 11.7 AdminServer
3. Stop OE 12 OpenEdge Explorer/Management (OEE/OEM)
4. Stop OE 12 AdminServer
5. Follow the article: How To Configure Multiple Versions of AdminServer To Be Run Concurrently since OpenEdge 10.1B
   1. Then fix all the port conflicts. It is recommended to change the OE 12 ports and leave the OE 11.7 ports as it is easier in OE 12 to change them all. The list is:
      1. RMI port for AdminServer (default is 20931)
      2. Remote management port for AdminServer (this is the primary issue, default is 6835))
      3. HTTP port for OEE/OEM (default is 9090)
      4. HTTPS port for OEE/OEM (default is 9443)
6. In OE 12 delete the configuration database (delete <OEMGMT_install_dir>/work/configdb) (optionally delete the graph cache database <OEMGMT_install_dir>/work/cachedb as well). The reason is that OE 12 OEE/OEM will try to bind to the AdminServer through port 6835 as default, it's hard-coded in the configdb. Even when we use a new -mgmtport from the cmd line or new port in management.properties, it makes no difference to the port 6835 we see in the OE Console under Options > Remote AdminServers.
7. Start OE 12 AdminServer
8. Start OE 12 OpenEdge Management
9. Login to OE 12. OEE/OEM, under Options, select Remote AdminServers
10. Click on edit and correct the port number to point to the 12 AdminServer remote management port
11. To manage OE 11.7 resources in OE 12 OEE/OEM, under 12 OEE/OEM:
    1. Start OE 11.7 AdminServer
    2. Under OE 12 OEE/OEM options menu select remote AdminServer
    3. Click on new
    4. Use “localhost” and the OE 11.7 remote management port (default is 6835)
12. To run OE 11.7 and 12 simultaneously
    1. Stop 11.7 Adminserver
    2. Make sure all ports are unique like -adminport, -port while starting 11.7 and 12.x
    3. In $DLC/properties/management.properties file add containerName=<other than hostname>
       containerName=117adminserver
    4. Start 11.7 AdminServer using the following command from proenv: proadsv -start
    5. Under OE 12 OEE/OEM options menu select remote AdminServer
    6. Click on new
    7. Use “localhost” and the OE 11.7 remote management port (default is 6835)
    8. Enter the system username and password and you will see the OE 11.7 Adminderver under the "Remote AdminServer Configuration"

Note: In OpenEdge 12, it's possible to change the default AdminServer port that OEE/OEM uses to connect to the local default AdminServer. It is not possible to change the host it connects to. In prior versions of OEE / OEM, it was not possible to change the default AdminServer port or the host.
 

Progress Article(s):
 How To Configure Multiple Versions of AdminServer To Be Run Concurrently since OpenEdge 10.1B
 How to change the default http listener port used by OpenEdge Management / Explorer ?
 How to configure multiple AdminServer versions to be run concurrently on Windows