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SME LINUX RAID 5

Offline AaronG

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SME LINUX RAID 5
« on: November 05, 2004, 12:12:46 PM »
Does SME support Software RAID 5?

Or on the other hand... if I had 3 SCSI or IDE hard drives with a PCI Raid Controller installed. Will it just interface directly with the RAID Controller and think it is just one big RAID5 volume?


Cheers
Aaron
...

Offline dmajwool

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SME LINUX RAID 5
« Reply #1 on: November 05, 2004, 02:49:21 PM »
SME supports PCI raid cards that manage Raid arrays.

I have SME6 running Raid5 on a 3ware escalade SATA PCI card.


HTH

David

Offline Reinhold

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SME LINUX RAID 5
« Reply #2 on: November 05, 2004, 06:57:32 PM »
Aaron,

For Raid5 you need at least 3 HDs ;-)
SME supports (Software) Raid directly from the kernel. :-D Support software incl. mdadm is part of the base-package.

Raid1 is even in the SME auto-setup.
Raid5 can be easily done ... just use the search button here... (incl. show all ...)

A hardware Raid controller has to be supported in the kernel or via (working!!!) driver (look for RH 6.3 hardware compatibility list).
3ware is the champion here...
With Highpoint, Promise and Silicon Magic "Raid"-controllers you'll be mostly on your own - or worse "out of luck".

This is a topic that is discussed once a week so you will find plenty in this forum.

Regards
Reinhold
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Offline Reinhold

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SME LINUX RAID 5
« Reply #3 on: November 05, 2004, 07:10:14 PM »
"small correction"
 - for Linux SOFTWARE RAID5 you could do it with just 3 partitions (not disks)
...just for the record and before I get comments :-o   (it's partition- not disk-based).

Nevertheless RAID5 starts to make sense with 3HDs and the more the better since you loose capacity of just 1 HD.
... also (in principle) HDs should each have an ide port of their own
(although I measured and found little speed difference from the SME serving across the net (an "S"me to be sure).)
The risk there when loosing the controller(s) seems lower in software raid with plain&simple IDE controller(s)
instead of using a proprietary Raid controller (I broke a hardware raid that was out of production ... usually terminal)

Regards
Reinhold
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