To replace the OH_RCT5023_SERVER modules in an APPolo Server Cluster, you will need a spare Rack i.e RFR 5018 with Rack Controller i.e RCT 5023-G and follow the steps below.

Primary Server:
  1.   Place the first replacement OH_RCT5023_SERVER module in the RCT 5023-G.
  2.   Instert the RCT5023 in to the Spare Rack Frame i.e RFR 5018.
  3.   Connect the RCT5023 via USB to a PC or Notebook running the latest APPolo GUI software.
  4.   Replace the default IP, SubnetMask and Standardgateway of the new OH_RCT5023_SERVER server with that of the primary server from the cluster under Settings TAB.
  5.   In case the login credentials of Admin for the cluster are changed or different as per default, Open a browser, type in the IP of the server and login using 
    User: admin     Password: lynx$admin under User Management.
  6.   Change the admin's password as in cluster.
  7.   Remove the OH_RCT5023_SERVER module from RCT 5023-G in the spare Rack.
  8.   Instert the OH_RCT5023_SERVER in to the appropriate RCT 5023-G in cluster.
  9.   Open the Connection Manager in APPolo GUI and right - click on the cluster (showing cluster error in red).
  10.   Click on Repair Cluster.
  11.   The Secondary Server will now become the Primary Server.
  
Secondary Server:

  1.   Place the second replacement OH_RCT5023_SERVER in the RCT 5023-G.
  2.   Instert the RCT 5023-G in to the Spare Rack Frame i.e RFR 5018.
  3.   Connect the RCT 5023-G via USB to a PC or Notebook running the latest APPolo GUI software.
  4.   Replace the default IP, SubnetMask and Standardgateway of the new OH_RCT5023_SERVER with that of the primary server from the cluster under Settings TAB.
  5.   In case the login credentials of Admin for the cluster are changed or different as per default, Open a browser, type in the IP of the server and login using
    User: admin  Password: lynx$admin under User Management.
  6.   Change the admin's password as in cluster.
  7.   Remove the OH_RCT5023_SERVER from RCT 5023-G in the spare Rack.
  8.   Instert the OH_RCT5023_SERVER in to the appropriate RCT in cluster.
  9.   Open the Connection Manager in APPolo GUI and right - click on the cluster (showing cluster error in red).
  10.   Click on Repair Cluster.
  11.   The Primary Server is now (again) the Secondary Server and vice versa.

 After the last step, the cluster must show the correct status in green.