LVM (was Re: why you have multiple partitions)

[Gregory K. Ruiz-Ade]

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

On Thursday 12 December 2002 17:12, Stewart Stremler wrote:

> Sure it is. I can take my SCSI drive, ethernet hub, or amplifier and
> speakers and plug 'em into another machine.  No worries.

Okay, there you have a point.  Perhaps someone should come up with a 
standardized way for writing RAID sets across the component devices, that all 
the RAID card manufacturers would support.

Hmm... Oh, yeah!  Pipe dream. :(

> Well, I don't do SCSI on x86 boxen anymore because the driver issues
> just aren't worth it.  Then again, I try not to do x86 boxen anymore
> anyway because I want to blow the damn things up. But that's just me.

never had any problems with the Adaptec and Mylex (formerly Buslogic) cards 
I've used.  Or the Symbios cards, but I've only ever used one of them.

[snip]

> Well, because I've been burned, and burned hard, with software RAID.
> Someone pulled the power plug, and the RAID was hosed. Utter and
> complete loss of data. (The system sync'd itself once a minute, and
> nobody was logged into the system.)

So, you want RAID, and you want it to be portable across systems.  Do you want 
it portable across OS's, to?  Back up to my comment about making standardized 
RAID writing formats.  Oh, and for the record, any hardware raid controller 
worth what you paid for it would have battery-backed cache on the controller, 
and would finish it's writes when next the system is powered up. :)

> I just don't trust software RAID.  Especially under Linux.

Neither do I, when dealing with IDE devices, but I've heard of people being 
quite happy with it (on both SCSI and IDE, go figure).

> What sort of RAID did you choose?

The Dell PowerEdge 4600's have a built-in Adaptec RAID controller that is 
actually quite smart in terms of configurability options.  We also got the 
split-backplane option, so half the drive bays are on a seperate SCSI channel 
than the other half, to eek out a little more performance.  We're doing 
RAID-10 (non-parity striping across sets of mirrors), with one half of each 
mirror set on either of the SCSI channels.  It's FAST.

> I keep looking at the external all-enclosed boxes. SCSI or firewire seem
> to be the most common solutions.  But they're several thousand $, it
> seems.

well, there's also fiberchannel, but that's buku $$$.  Then stand-alone SCSI 
RAID enclosures are indeedy pricey, at anywhere from $1500-$4500, for 
anywhere from 4 to 8 HD's, also depending on what kind of capabilities you 
want.  There are models that take IDE drives, and models that take SCSI 
drives, and both variants act like a single SCSI device and connect via 
UltraLVD SCSI to a host computer.  *that* box you can take and plug into 
whatever system you want.  It's hardware RAID, but with the managemetn 
software built into a little control panel on the front, and removed from the 
SCSI host adapter.

I'd love to have one of them...  but for $3k I can do a lot of more important 
things. :(

- -- 
Gregory K. Ade <gkade at bigbrother.net>
http://bigbrother.net/~gkade
OpenPGP Key ID: EAF4844B  keyserver: pgpkeys.mit.edu
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.0.7 (GNU/Linux)

iD8DBQE9+UiWeQUEYOr0hEsRAjwvAJ0e4OGJhDSvfBFEQJEUOpFzEfdPfQCgj1vS
8dFAnX9ebcI42N38a30tog8=
=1lj0
-----END PGP SIGNATURE-----