PDA

View Full Version : Why not RAID 5?



approd
06-03-2004, 07:47 PM
I just experienced a terrible catastrophe with my toaster system.
My IDE hard drive died. I was able to recover the data at great expense but what did not come back was my SCSI array.

I set it up as recommended with an adaptec controller card and 4 seagate 36 GB drives striped RAID 0 through windows disk manager.

When I lost the OS as a result of losing the IDE drive, my new Windows 2K installation could not recongnise the stripped set.

Unless someone has an idea to resolve this I will be forced to wipe the data on the SCSI array and remake the RAID 0 set.

A microsoft service guy recommeded I use a hardware controller and set up the array as RAID 5. He claims I would not lose speed. I understand, however, Newtek does not recommed this for the Video Toaster because hardware controllers operate on burst speed rather than the sustained rates required for video.

RAID 5 would give me a safety net because losing the OS would not result in my losing the data on the array. But will doing this impare or defeat the ability to smoothly stream my video?

Would RAID 3 help?

Jim Capillo
06-03-2004, 08:33 PM
Try this before you format anything: http://vbulletin.newtek.com/showthread.php?s=&threadid=23944&highlight=raid

You can thank Scott Bates if it works - this place is really a wealth of info :)

robewil
06-03-2004, 10:10 PM
Originally posted by approd
A microsoft service guy recommeded I use a hardware controller and set up the array as RAID 5. He claims I would not lose speed The Microsoft service guy is most definitely incorrect. This is why RAID 5 is generally not recommended for video applications. RAIDs are for two purposes, speed and redundancy and their values are inversely proportional. RAID 0 is strictly for speed, it has no redundancy while RAID 5 contains enough redundancy where one or more drives can be removed or go down and the RAID still functions. But the cost of RAID 5 is speed and capacity. You only get a portion of the total capacity of the hard drives in a RAID 5 setup.

Rich Deustachio
06-03-2004, 10:52 PM
I use an external 800 firewire drive to back up projects in progress. It moves 80 gigs in an hour.

Lightwolf
06-04-2004, 02:59 AM
A good compromise between speed and safety seems to be RAID-3, but controller that support it seem to be hard to come by.

Cheers,
Mike

mgrusin
06-04-2004, 12:22 PM
There's also something called "RAID 0+1" which is stripe + mirror. Theoretically as fast as stripe and as robust as mirror, but you need 2X the drives. :(

-MG.

SCS
06-04-2004, 01:15 PM
Is RAID 0+1 hardware only, or can it be accessed with WinXP software (Server version?)?

mgrusin
06-04-2004, 03:38 PM
I've seen it as a hardware option from various makers, can't remember if I've seen it within Windows Disk Manager (guessing not). I'll take a look next time I'm editing.

-MG.

ted
06-05-2004, 01:09 PM
Huge Systems has a nice Raid 3 option. 200mbs at raid 3. BUT, I had to send mine back because it requires PCI Express to get that kind of performance.

rclarkecva
06-29-2004, 04:23 PM
Right Click on My computer>manage>disk management.
Right click on the "foreign disk" on the graphical representation on the left side.
and select "import foreign disks"
don't use a RAID controller as this will bottle-neck your data stream through put.
All true RAID controllers use memory to buffer the data stream.
You will slow down to a crawl on the through-put.

tmon
07-08-2004, 03:10 PM
A previous discussion:

http://vbulletin.newtek.com/showthread.php?s=&threadid=8698