SuperMicro 5013

[John Rowan]

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 at rownetco.com
Web:	http://www.rownetco.com