Hardware Understanding Raid

I was think JBOD over raid0 so that even if the two disks in one mirror pair failed, you wouldn't lose everything.
Even so, you would still lose some which wouldn't be much use. :/

 

Nice article maybe could've touched on a bit about JBOD I know it's not technically a RAID solution but almost all consumer RAID controllers offer it and it would've flowed with the "what's best for home use" theme.

 

The more hard drives you have the more succeptible you are to hard drive failure and thus the more expensive your solution.

Google proved that hard drives fail incosistently, there's no way of detecting an imminent failure to a significant enough extent, there's no specific brand which fails the most, it's just which end users are most vocal about their problems.

 

"Currently 2.5” 15k RPM drives are the crème de la crème of high I/O performane, and you’re going to need more than one of them as the largest available is a mere 73GB. "

you sure about that?

cos im writing this with an array of 16 146.8 gig 15K 2.5 RPM sas drives sitting infront of me, in the same place it has done for the last 6 months.

 

Thank you for this article, it quite perfectly explains the most important things you need to know about RAID to understand how it works (adding the details about XOR parity generation has been a good idea)!

It just so happens to be, that i finished building my own RAID-6 array a few days ago. I was using two RAID-5 arrays before, and i started using RAID as soon as it hit the desktop market with levels 0 and 1 in the beginning.

My Controllers so far: Promise FastTrak 66 RAID-0, Intel ICH RAID-0, nVidia nForce4i RAID-0, Promise SuperTrak SX6000 RAID-5 (two array, first with 120GB WD disks, then migrated to 300GB MaxLines), finally a 3Ware 9650SE-8LPML.

I have now switched to 3Ware because there already are Vista Beta Drivers, and Final Drivers to be released soon (and of course because of FAR higher performance, higher fault tolerance, more space and so on).

Current Array:
3Ware 9650SE-8LMPL with Battery Backup Unit 03
8 x Hitachi 7K1000 1TB HDDs

For those who are interested, here are a few Benchmarks and Pics of this array. Read speed is around the 100-160MB/s mark, writes are around the 50MB/s mark (NTFS compression is active). Read scores can be ignored for ATTO Disk Benchmark, as reads were unfortunately cached here..

Master Boot Records only have 32-Bit Addressing and physical drives have 512 byte sectors, that makes a maximum of 2TB for physical drives. So larger arrays have to be split up into smaller <=2TB pieces, that can be put together again by using dynamic discs and a "JBOD" volume in Windows XP:




POST:


Cooling by Antec HDCS (2 temp controlled Y.S. Tech Fans, two temp sensors, massive aluminium block):



The whole thing built in:


HDTach Quick Bench, 8MB Zones:


HDTach Long Bench, 32MB Zones:


ATTO Disk Bench:


HD Tune (sorry, got no thumbnail here):


It is very comfortable to have ALL your data, be it your DVD Movies or Games, be it music or just a whole lot of old files accessible by just a few clicks! I love huge RAID Arrays, oh yes.

 

Thank you. I might have written it in a bad way, but that was exactly what I was trying to point out. Many think that just because you got a RAID1 array set up, you don't need to do backups.

 

but once you start piling up the terrabytes it starts getting hard to backup for less then the array cost you

 

Been curious for years but just hadn't got round to researching. Thank you for the great info

 

seriously, holy mother of necrothreads.