We recently purchased a number of 3TB drives, only to realize later it was for a Dell server with a PERC 6i, and that >2TB drives are not supported. Based on the amount we paid though, the restocking fee along with the cost of the 2TB drives is about the same.
All the questions here and on Google address that the PERC 5i and 6i controllers cannot recognize greater than 2TB hard drives. Dell has this to say: "NO earlier controllers, such as the PERC4/5/6, SAS5/6 (or ANY other Dell controller not mentioned) have this support and in some cases, even though you may be able to see the drive, this has NOT been tested or validated, so possible data loss could be experienced."
However, if we format the 3TB drives as 2TB drives on the PERC controller and put them in an array (that is, not use them as 3TB drives at all), are there issues we will run into in terms of reliability, data integrity or MTBF? Or is it like putting more than 4 gigs of RAM in a 32 bit OS, in that there is more storage but it just isn't accessible?
Best Answer
In my experience, it's like putting more than 4 GB or RAM into a 32 bit OS, in that the additional space is simply not usable.
There is one major difference though, in that if you have support through Dell, and you use unsupported hardware (like a 3 TB drive), you will be invalidating your support, and may very well be told "no" if you need to call in about a an issue related to the PERC card, storage array or drives (and most anything can be stretched into being "related" to those components, if they want to badly enough).
It would really be best to just replace the 3TB drives with 2TB ones. Yeah, the price is about the same, but if you're not going to be able to use the additional TB of disk space, the only functional difference is that one's supported, and one is unsupported and "has NOT been tested or validated, so possible data loss could be experienced." The better choice is clearly the supported one that's otherwise functionally identical to the unsupported one.