Automatic discovery of servers without the use of IP ranges

Hi,

We are looking for ideas on how to manage all our Dell servers. I was thinking of a script on the servers running OMSA that will add them to OME. Is that possible?

Here is the important info:
* Our IP ranges contains 60.000.000 IP adresses, so automatic discovery is out of the question
* We are running Windows server 2003, 2008, 2008R2, 2012, Linux distributions (For VMware and XenServers)
* There are about 1.000 physical Dell servers (M610 and M620)
* Most of the servers are in our datacenter.
* We can use as many servers as we want for Openmanage, but they all need to be managed from the same webpage (maybe if there is an option to split the workload between servers)

We have tried to figure this out for some years now, but we still don't know what the best solution here is and would appreciate any help on the matter.