Subject: Re: fiber channel recommendations?
To: None <tech-kern@NetBSD.org>
From: George Georgalis <george@galis.org>
List: tech-kern
Date: 01/10/2007 00:28:49
On Tue, Jan 09, 2007 at 02:17:00PM -0800, Bill Studenmund wrote:
>On Tue, Jan 09, 2007 at 04:11:10PM -0500, George Georgalis wrote:
>> On Tue, Jan 09, 2007 at 02:27:42PM -0500, George Georgalis wrote:
>> >Reliability, NetBSD compatibility (ongoing) and the usual apply.
>> >Price is not too important but it should be reasonable, eg I'm
>> >expecting 200 - $550.
>
>I think $500 is an inexpensive price for an FC card.
thinking about it, but not yet shopping, yes, I guess it's
reasonable for FC to cost a bit more.
>> >Per PCI/SCSI host adapters in the device compatability page, I see
>> >LSI and the mpt driver.
>> >
>> >Is that a good choice? Do you just plug these things in and use
>> >them? What device nodes will be used?
>>
>> Turns out the device I'm interested in uses scsi hba...
>> I'm still curious if there is anything different using fc?
>
>Note: Fibre Channel uses SCSI for the commands, so your use of "scsi hba"
>is a bit weird; in a (strong) way, a Fibre Channel card is a scsi hba. :-)
>
>I assume you're really talking about the parallel SCSI above. It's called
>SPI (SCSI Parallel Interface), or parallel SCSI,when the difference
>matters.
>
>Many cards use the same interface to the host for Fibre Channel as for
>SPI. So the kernel won't care about the difference. We will find scsibus's
>and sd drives and so on on the SAN.
I may have not been completely clear. it turns out the
raid enclosure I'm looking at, the Comet SATA II 16eU from
http://caeneng.com/ does have a scsi u320 interface, so no FC
needed.
SPI, that I'm not sure what is what. So the data is sent serial
but the devices are wired parallel? Is there such a thing as non
SPI SCSI?
Apparently a u320 scsi host controller may see a JBOD (individual
disks) on the external enclosure, so a u320 SCSI HBA was
recommended so the host just sees the constructed raid media.
I think that makes sense, but the difference of a u320 HBC
or non HBC is a bit confusing.
// George
--
George Georgalis, systems architect, administrator <IXOYE><