I am using HP Proliant ML 370G5 server with windows 2003 OS for the role of file server. It contains six HDD (Hot swapping). Out of six, four (136.7*4) HDD has been configured for Raid 5 and rest two (68*2) as mirroring (Raid 1+0) which is dedicated for OS. Now i want to add one more hard disk in raid 5 due to low space. Is it advicable to add new HDD in existing raid 5? Please assist.