ILO default username always Administrator

As you say, the HSI (Hardware Support Information?) Tag refers to the machine itself, and the MP (Management Processor) Tag the iLO.

xmldata?item=CpqKey will return licensing information such as advanced license key, install date etc. As far as I know these are the only two documented XML queries and I suspect by virtue of the name (cpq - compaq?), that they are a legacy item in the iLOs.

As far as network discovery, many scripts are written to see if they get a valid result from the URLs above - if not, then it is not an iLO as far as the script it concerned.

One such example for iLO discovery is located at http://blog.nachotech.com/?p=63 and uses a BASH script. I've written powershell scripts that do audits of iLO devices and they too scrape data from the xml URL.

When you first turn the server on, there's a a section during startup that says "Push F8 to enter iLO Configuration" (might be some other function key). Do that and fill in the network information and setup a login.

Once that's done, open a web browser at your computer and enter the IP you configured. It should be very self explanatory from there.

The iLO configuration is not stored on disk, and not in the BIOS, so there's a decent chance it isn't clear. Also, how your VPN works and how to use it is completely outside the scope of using iLO.