Just figured out what I was doing wrong.  After selecting the ISO, I was not clicking the box under 'mapped'.  I did not see anything in the Dell iDRAC6 where this step is stated.  It kept talking about selecting the ISO.  The detail of the Mapped option did not state that this is how it is offered to the BIOS during boot up.  I thought mapped just meant it was offered up to the OS. Thank you all. 
Hello all, I am trying to perform an installation of a R310 with Red Hat.  I am able to access the iDRAC6 and configure the virtual media.  As this has a copy of Red Hat on it, I confirmed I could share the ISO through the virtual media. Now I want to boot off the new ISO image that is in connected through virtual media.  I have set Console/Media, Virtual Media to be set to all Boot Once.  I then open Launch Virtual Console , click Virtual Media and then Add Image and select the Red Hat image. As I have read through the Dell document, I then just need to go to Setup and select  Virtual CD/DVD/ISO for First Boot Drive, make sure Boot Once is selected and click Apply.  The lst step according to the documentation is to power cycle the server. I do.  the server shutsdown cleanly.  I get No Signal.  Watch the server start.  And the old copy of Red Hat start. Am I missing a step?  As the Virtual Manager has both the DVD drive (which has nothing in it) and the ISO, could it be looking at the DVD and see nothing and just continue through the normal boot? Any help would be greatfully appreciated.
iDRAC6 Virtual Media and Red Hat ISO