Pat Regan on 1 Nov 2005 13:05:41 -0000

[Date Prev] [Date Next] [Thread Prev] [Thread Next] [Date Index] [Thread Index]

Re: [PLUG] RAID Backup Server

Edmund Goppelt wrote:
> On Mon, Oct 31, 2005 at 10:00:22AM -0500, Pat Regan wrote:
>> I am also a big fan of 3ware PATA and SATA RAID controllers.  They are a
>> bit pricey, but less hassle (and in most cases, faster) than software
>> RAID.
> Since the 3ware RAID cards cost between $300-$400, I'm inclined to go
> the software route.  Why less hassle?  Don't you have to fiddle with
> custom kernel drivers?

I am probably somewhat exaggerating how much hassle software RAID is
these days.  I notice the new Debian installer lets you set up MD and
LVM during installation.  I had problems testing it in a VM.  MD seemed
to work fine, but when I tried to configure LVM...  It would let me
create a volume group with no errors, but it wouldn't let me create any
logical volumes because the VG didn't seem to exist.

I think the bigger advantage of the 3ware hardware is speed.  If you do
mirroring in software (RAID 1 and RAID 10) you push twice as much data
over the PCI bus and you use double the CPU time writing the data
(especially in the case of IDE).  The 3ware driver works like a SCSI

There are no custom kernel drivers to worry about.  The driver has been
in mainline for many years, and I as far as I know any remotely modern
distro has the driver on the boot cd.

I have a very old card in my desktop (I think it is an original 7800, 8
port full lenght 64-bit PCI card).  They have almost non-existent cache,
and provide horrible RAID 5 performance.  It is my understanding that
the current generation of cards are light years ahead of the old ones
for RAID 5.  For RAID 0, 1, or 10 it is VERY hard to beat a 3ware card.  :)


Attachment: signature.asc
Description: OpenPGP digital signature

Philadelphia Linux Users Group         --
Announcements -
General Discussion  --