Thanks for response. Yes we can do, actual problem is I want to boot my server with flash drive, I don't want to use harddisk for OS, HDD for storage and flashdrive for OS. 
hello sir,               I have a new question about dell power-edge, actually i wanted to know this server is working on only raid configuration and for the safety purpose of data, are we able to use a flash drive for booting purpose( os ex: esxi,linux,windows) of server so that data will be store in SAS drive and OS will be separate in flash drive ? please clear my doubt...thanks
Booting options in dell r610 poweredge with perc 6/i raid controller