We can find HP valid Onboard Administrators list in the subnet by using the HP cmdlet Powershell script .
Download the HP cmdlet from the below link .
http://www8.hp.com/us/en/products/server-software/product-detail.html?oid=5440657#!tab=features
Install the HPOACmdlets-x64.msi and look for the pdf for the installation steps.
Get-Help *hp* – It will show all the commands related to the HP
Get-Help *hpoa* – It will show all the commands related to the HP-onboard administrator.
The Find-HPOA cmdlet lists valid Onboard Administrators in the subnet provided. You must provide the subnet in which the Onboard Administrators have to be searched.
Download the script from the below location.
Related links:
Powershell Script to get the specified direct attached blade device serial number
Powershell script to find the HP Enclosure information
Powershell script to find the current status of the specified HP Enclosure Fan
Powershell script to find the basic health and status of the HP Enclosure
Powershell to get the graph report of VMware VMs configured Memory.
Techbrainblog 
Pingback: Powershell Script to update the ilo firmware from the list of IPs. | Techbrainblog
Pingback: Powershell script to update the Onboard Administrator firmware. | Techbrainblog