Originally, I was going to title my rant here "Best Buy Sucks".  A quick google search , however, shows that neither the phrase nor the sentiment is particularly unique.  I've read a lot of horror stories about people and their experiences with this particular retail chain.  One of my favorite ones (here ) was about a guy who refused to allow his bag to be searched at exit - they "pinned" him to his car and called the police.  He had not stolen anything.  This one was a fun read, and got coverage on some larger websites.  It is about a girl who was "cheated" out of an IPOD by Best Buy.  The last one I'll highlight is this one , where a guy bought a hard drive and recieved a box of bathroom tiles.  The heartwarming part of that story is where Best Buy wouldn't refund payment.

Now, I don't know if these are true or not, but I do know that I have had my own altercation with their famously friendly customer service.  The details of this interaction are outlined below. 

The EMC Clariion storage array treats the first 5 disks in the first tray of disk special.  This is what is known as the "vault", and it is used as a dumping ground for cache in the event of certain failures that threaten the safety of cache.  EMC Best Practices suggest that you do not use these drives for anything other than the vault if your array is large enough to reasonably do this.  They also suggest not mixing these drives with drives from other raid groups.  The reason for this is that the vault drives appear smaller than a non-vault drive of the same size.  This happens because some of these drives are reserved for use by the Clariions.  Mixing them with other drives makes all the drives in the mixed raid group appear smaller, thus wasting space from every drive in the shared raid group.

Based on these best practices, I will generally get the smallest fibre channel drives availble to use for the vault, and then put those drives alone in a raid group.  I typically then bind a LUN to fill up this entire RAID group so that the space doesn't look available.

Assuming you have NAVI CLI installed, here is a quick script you can use to setup your vault drives like this.

navicli -h 10.80.200.35 createrg 0 0_0_0 0_0_1 0_0_2 0_0_3 0_0_4 -rm no -pri high
navicli -h 10.80.200.35 bind r5 0 -rg 0