Is 500 a typo ... did you mean a 900GB hot-spare?  If so, then yes.  If not, then know that any hot-spare must be at least as large as the smallest disk in the array to be eligible as a hot-spare.  Any hot-spare for LUN's 1 and 2 must be a 900GB or larger SAS drive.
Hi,   I'm looking at buying a Poweredge R720 with 11 SAS 2.5 inch 900 GB drives and 5 SAS 2.5 inch 146 GB drives with a Perc H310 RAID controller. What I'd like to do is the following: Setup config as the following RAID 10 - using 10 of the 900GB drives, with the 11th as a hot spare RAID 1 - using 2 of the 146GB drives, with 1 hot spare  RAID 1 - using the remaining 146GB drives Can someone tell me if this is possible with the drives, controller and RAID options I'm looking at? Thanks
Hardware RAID options on a Poweredge R720