[Raid 5]

The read performance of RAID6 is the same as RAID5. It is only the writes that can have a lower performance It needs to do a few more calculations than RAID5 does as it keeps multiple parity blocks. If you have good RAID controller then the extra calculations will be done in custom hardware and RAID6 will be just as quick as RAID5 (the disk writes take up the time not the calculations).

If you are using software RAID though it would be worth taking sometime to think about performance issues and if you want more redundancy or write performance as Infiltrator's post.

Unfortunatly Freenas doesnt support Raid 6 at this time not sure it ever will, it is the only os I have found which is free and has UPNP support, I was going to use Ubuntu and use Mediatomb but I found configuring the disks to be a pain in the ass maybe it might have something to do with the fact that I dont know linux a great deal! lol also the drives are in a software raid I dont have a raid controller, thanks for your help :-)

[Raid 5]

Forgot to mention, many RAID controllers don't support volumes above 2TB, that is some thing else that needs to be determined.

Thanks guys I thought that might have been the case, thanks a lot for your help most greatfull:-)

:)

[Raid 5]

I am hoping someone can help I have a pc which I have made into a Media Server Running Freenas and it works really well anyway I have just added 2 more HDD's to the system, so I now have 2 500GB drives and 2 1.5TB Drive, I have configured it into a raid 5. my problem is that the total space is 4TB but it is only giving me 1.3TB of usable space, Am I wrong in thinking that it should not need to use 2.7TB for Rundentcy, I thought I would of had at least 2TB or usable space. Or will I need 4 identical drives, hope someone can help

James