"i see only one hard with one drive (1 tera). How to know that raid 1 is installed and working properly?" Sounds like it is working fine.  With hardware RAID, the controller groups the physical disks together into an array and creates a "logical" or "virtual" disk.  It is ONLY that virtual disk that the OS sees, NOT the individual physical disks.  You can install OMSA (OpenManage Server Administrator) to monitor and manage RAID, including the individual physical disks, but if otherwise, if you want to test the RAID, pull a drive while the OS is running.  If the OS crashes, it's not working.  If it stays up and running, then it is working.  I would recommend the OMSA route.
Hello all, I want to install Raid 1 on server T320, but i don't know how? I try some steps before by ctrl+ R and make VD, then add the two HDD(1 Tera for each) to the VD. After that i install windows server 2012, and i see only one hard with one drive (1 tera). How to know that raid 1 is installed and working properly? If you can help with steps to installing and screen shots if available will be nice. Thank you all . 
How to configure raid 1 in PowerEdge T320