[blue68f100]

You have to use another snap. But this is true with most any RAID system. The reason Backup's are Still Required.

If you use a UPS HW failures are very very low with these units. The 4000 has a history of bad power supplies. Well not bad, unless you over load them. The new larger HD pull more current on the 12 v buss, to spin the drives up. This only last for a few seconds. So you do not want to be turning these off and on daily. They are design for 24/7 operation.

Raid 5 is a redundant array, that waste less space than raid1.

I always recommend testing your systems. If you find out you have a hw v1 or 2 you will run into a problem if a drive fails. It requires a simple IDE cable mod to correct the proplem. So check your HW version, usually it's posted with -00x after the part no.

So before you put your system on line, test your system by failing drive 2 and see if it reports correctly. Then go through the recovery process, power down and re connect the drive. These are NOT HOTSWAP units. The you will know what to do if a drive does fail.

I hope this answered your question.