Back up the customized files on the Access Manager 4.5.x setup.
Note down the IP address of Windows Identity Server.
Stop and remove Identity Server from the cluster on the Windows machine.
Delete Identity Server that is removed from the Identity Servers cluster.
Switch off the Windows machine.
On the RHEL machine, change the IP address to the IP address of Windows Identity Server that you noted in step 2.
On the RHEL machine, use the NetIQ Access Manager 5.0.x installer to install Identity Server.
Add 5.0.x Identity Server to the existing Identity Server cluster in 5.0.x Administration Console on RHEL.
Update Identity Server and apply changes.
Restore customized files from the backup taken earlier.
Back up the customized files on the Access Manager 4.5.x setup.
Use the NetIQ Access Manager 5.0.x installer to install Identity Server on the RHEL machine.
Add Identity Server to the existing Identity Server cluster in 5.0.x Administration Console on RHEL.
Update Identity Server and apply changes.
Restore any customized files from the backup taken earlier.
Delete older Identity Servers on the Windows machine.