"Transparent" IDE RAID controller
Actually... come to think of it... I wonder if ANY RAID controller does
- appears to be just ONE hard disk (eg. hda) to the server
- actually has 2 or more hard disks connected to the RAID controller (but
only shows up as one to the OS)
- if in RAID1 mode (mirroring), if one disk fails, the controller
AUTOMATICALLY uses the remaining hard disk(s), and perhaps a LED could
light up, indicating a problem with a disk. Once a new disk is connected,
the RAID controller automatically rebuilds
- if in other modes, does 99% of operations by itself with no intervention
required by the OS (auto rebuilds, etc.) except manual things like
replacing a dead drive
This would mean the RAID controller is, more or less, OS independent, and
requires no OS level software to make it run, thus making it a
"transparent" RAID controller.
I've pondered this for a while, and i'm certainly no hardware raid expert
but it appears like a workable and doable solution.
So, for example if i mounted hda, the controller would transparently
activate both the drives (if you are running raid1 with 2 hds). A cp to
hda would tell the controller to do a normal cp to hda on the OS level,
but the "transparent" hardware raid controller would know that it is
running in raid1 mode and automatically cp the file(s) to both hard disks.
After cping the file to both hard disks, it would tell the OS, like a
regular hd controller, that it had finished the operation, and thus the OS
would not need to know that the file(s) were actually copied to 2
different hard disks.
If there is such a solution on the market... I haven't seen it. But
perhaps you could tell me WHY there is no such product when it seems like
it would solve many problems with software/hardware incompatibilities, and
would solve many many admin's troubles?
Failing that... is there ANY product on the market that does plain
hardware level mirroring (for IDE)? What we do now is (essentially) cp hda
to hdb every 24 hours, so in the case of a major hd failure on hda, we
simply swap hdb over to hda and continue running (but with stuff that
could be up to 24 hours old). What would a solution be to make it so hdb
is never so out of date with hda, or perhaps even a LIVE copy (considering
the above proposed transparent hardware raid, and without causing massive
load during the day)?
I think this is something many admins have to consider... what is YOUR
solution to this?
----- Original Message -----
From: "Jesse Molina" <firstname.lastname@example.org>
To: <email@example.com>; "Debian-Isp" <firstname.lastname@example.org>
Sent: Tuesday, November 06, 2001 9:41 AM
Subject: RE: hardware raid
> If you are looking for Ultra 160 SCSI, the Mylex AcceleRAID 170 may be
> something that you want. I recent purchased about 30 of these cards for
> RAID 1 solution for some rack servers. They work pretty good. RAID0,
> RAID1, Spanning (JBOD), RAID5. You can backup and restore the
> configuration to a floppy disk, the BIOS interface is fairly nice and
> simple. Rebuilding takes awhile, but no big deal.
> They also make an AcceleRAID 170LP, a low-profile PCI card. Pretty
> AMI recently sold all of their RAID card business to LSI Logic, this
> getting some of the AMI cards a bit difficult right now. Otherwise, I
> also recommend the AMI Express 500.
> If you are looking for IDE, I have no comment there.
> # Jesse Molina lanner, Snow
> # Network Engineer Maximum Charisma Studios Inc.
> # email@example.com 1.303.432.0286
> # end of sig
> > -----Original Message-----
> > From: Andrew Kaplan [mailto:firstname.lastname@example.org]
> > Sent: Monday, November 05, 2001 3:20 PM
> > To: Debian-Isp
> > Subject: hardware raid
> > I'm looking for a good hardware raid 1 (mirroring) solution
> > for Debian. Will
> > the promise cards work with Debian or is there a better
> > solution thanks.
> > Andrew P. Kaplan
> > Network Administrator
> > CyberShore, Inc.
> > http://www.cshore.com
> > "I couldn't give him advice in business and he couldn't give me
> > advice in technology." --Linus Torvalds, about why he wouldn't
> > be interested in meeting Bill Gates.
> > > -----Original Message-----
> > > From: Craigsc [mailto:email@example.com]
> > > Sent: Monday, November 05, 2001 4:17 AM
> > > To: Debian-Isp
> > > Subject: VIM
> > >
> > >
> > > H
> > >
> > >
> > > --
> > > To UNSUBSCRIBE, email to firstname.lastname@example.org
> > > with a subject of "unsubscribe". Trouble? Contact
> > > email@example.com
> > >
> > >
> > > ---
> > > Incoming mail is certified Virus Free.
> > > Checked by AVG anti-virus system (http://www.grisoft.com).
> > > Version: 6.0.286 / Virus Database: 152 - Release Date: 10/9/01
> > >
> > ---
> > Outgoing mail is certified Virus Free.
> > Checked by AVG anti-virus system (http://www.grisoft.com).
> > Version: 6.0.286 / Virus Database: 152 - Release Date: 10/9/01
> > --
> > To UNSUBSCRIBE, email to firstname.lastname@example.org
> > with a subject of "unsubscribe". Trouble? Contact
> > email@example.com
> To UNSUBSCRIBE, email to firstname.lastname@example.org
> with a subject of "unsubscribe". Trouble? Contact