Edward Dekkers wrote:
I know this problem is specific to Raining Data's app but suggestions
from this group on how to protect the RAW partition since I can't use
the Intel software RAID would be welcome.
Last question though, why is the Intel RAID for Serial ATA which
appears during POST considered software RAID? I would think this to
be hardware RAID.
Not...really...
Think PCI WinModems.
Although the modem is a piece of hardware you stick into your PCI
socket, really all the hardware does is simply digital to analogue
conversion.
This is not enough to make the PCI card behave like a modem. To do
that, the "brains" (and I say that VERY lightly) who came up with the
idea of WinModems used the driver for Windows as the brains behind the
card. All the stuff that for years was implemented in external serial
modems (and some internal ISA cards that actually created a RAW comm.
port) in hardware, had now been taken over by the software.
Reasons for this are of course cost - the WinModems cost less than
half usually of TRUE hardware modems. The "Firmware" never needs
updating. When you update the driver, you're auto magically updating
the firmware. Today's processors are fast enough to perform all these
things in software without taking a real performance hit.
This is also the reasons why it took so long for WinModems to work
under Linux. There was no software. Previous modems did not need it,
and now they did.
Intel RAID - same thing. The "hardware" chipset on the board really is
just the bare minimum to get the drives to announce themselves like
mirrored or striped sets. The rest is all done in software.
Now, I DO know, being a GID that there ARE Linux drivers for RAID. So
you CAN get it working, however as most people here will tell you, it
will be better for Linux to handle RAID in this case independent of
the Intel RAID. I would tend to agree at this point.
That's it in a nutshell.
As far as Pick, I don't know a hell of a lot about it. I have one
customer here in Australia only that runs it, and I CANNOT get them to
switch. I'm sure what Pick does can be done as well with an SQL
server, and would certainly prefer it, as it would be far easier to
administrate from a Linux perspective.
As far as the RAW format.
Theory says it shouldn't matter how the partition is formatted (or
not). The RAID should work regardless as it sits "beneath" partitions
and file systems. i.e. it is at a lower level.
However, having no experience with running Pick this way, you really
shouldn't take my word as gospel.
Regards,
Ed.
Ed, thanks for your reply. Since my post I have downloaded CentOS,
burned CDs and built the machine with this RHES repackaged operating
system. First impressions is it looks identical to FC4 but I only
worked with it for 4 hours last night, 2 of those hours were installing
/ customizing Pick and restoring production data. I've never worked
with Linux RAID. All prior RAID experience was via hardware in Compaq
servers where the Smart2/P or later type controllers presented the
RAIDed drives as one disk to the OS. I have to update my client on the
status of the build today. At this point any changes in BIOS to the
RAID definitions will erase my efforts so far. I suspected and
confirmed that when I tried changing back to RAID1 (mirrored) after I
had Linux working. After the change I ended up with something like
Operating System not found. I tried removing RAID1 and all was gone. I
knew those were the risks when I started tinkering.
Oh, this is my first exposure to Hyperthreading. It's interesting to
run top on a single processor machine and have it display two different
levels of utilization.
--
John Rowan
Rownetco, Inc.
Office: 973 697 8019
Fax: 973 697 4443
Cell: 973 229 5742
E-Mail: rowan@xxxxxxxxxxxx
Web: http://www.rownetco.com
