Date: Fri, 2 Mar 2007 23:09:50 +0100 From: Baurzhan Ismagulov <ibr@radix50.net> To: aic7xxx@freebsd.org Subject: Re: Adaptec 2940UW with Fujitsu MAN3184M Message-ID: <20070302220950.GD7331@radix50.net> In-Reply-To: <45E77B30.2090505@paralan.com> References: <20070228204034.GA2379@radix50.net> <45E602B3.2020306@paralan.com> <20070228233314.GA7348@radix50.net> <45E77B30.2090505@paralan.com>
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Hello Marc,
On Thu, Mar 01, 2007 at 05:17:36PM -0800, Marc D. Brooks wrote:
> >>It is possible that even though the 2940UW initially negotiates for
> >>Ultra, the domain validation forces it to the slower rate due to
> >>issues seen with the communications.
> >Any way to see those at the Linux administrator level?
>
> The type of SCSI the device and HBA supports is usually in the
> specifications for the device and the HBA. Some BIOS implementations may
> report the Single Ended, LVD or HVD bus type somewhere in its menus. For
> Adaptec, in their model number they have the bus type encoded. 2940 =
> Single Ended, 2944 = HVD, 29160 = LVD Ultra160, 29320 = LVD Ultra320.
> For the Device you are using, I did a search for the data sheet for the
> device and found out that it claimed to be Ultra160 device (It
> automatically has to be LVD capable to do Ultra160).
Thanks for the explanation! But how can I find out what factors drive
the bus speed to 10 MHz?
> >The card is branded Siemens-Nixdorf, I don't see the usual Ctrl-A
> >prompt. I've seen older SNI controllers, all settings were accessible
> >from the main BIOS. So, I guess I can't check this.
...
> The card you have may be set to max out at Fast operation in the
> firmware for that OEM card.
...
> The OEM "Siemens" Factory Settings may be causing the negotiations
> with the drive to not go at the Ultra speed, or in performng domain
> validation, it had set to go slower in order to operate without
> transmission errors.
I see User set to 40 MB/s in /proc/scsi/aic7xxx/0, so I think BIOS
settings are not the limiting factor.
> >The "when" part above is strange. Now I don't have the drive connected,
> >aic7xxx is loaded, but I see neither kernel messages in log, nor
> >/proc/aic7xxx.
...
> Was the cable disconnected at the Adaptec, or at the drive package?
Sorry, the file name is /proc/scsi/aic7xxx, I hadn't looked good enough.
> >1.2 m, four 68-pin connectors for drives, black box at the end saying
> >"Foxconn" and "Ultra 320" (terminator?), the drive connected to the last
> >entry before the terminator ("far" from the controller).
>
> I do not have any direct experience with "Foxconn". It sounds like you
> have a raid package or JBOD with a backplane. The terminator is
> installed at the end of the backplane?
That isn't a backplane, that's a round cable with a black box at the
end.
> The Adaptec can have termination set or unset through the BIOS menus,
> but I do not know what it would take to do that or if its possible with
> the Siemens OEM version card you have.
Ah. Again.
But if the controller side is not automatically terminated, would the
drive function reliably? I've built OpenEmbedded on this drive without
problems (4 GB after compilation, many hours on my 1.5-GHz system). A
similar configuration with a bad adapter didn't last 10 min. Can I
somehow measure whether the controller has the termination enabled?
> The similar Adapte you mention is sill a Single Ended one. The stability
> problems are most likely associated more with Ultra Speed Single Ended
> SCSI than with the card itself. Ultra speed communications with Single
> Ended devices were at the limit of the physical bus capabilities and a
> lot of things could go wrong with it.
...
> The only thing you really have to watch out for is improperly made
> SCSI round cables. I would recommend that you swtch to an LVD version
> (the 29160 should be fine) of a generic Adaptec controller, since the
> SCA adapter, the Box that the adapter is in, and the Drive are made to
> be able to support it.
That is exactly the problem: Everything is made for at least SE Ultra,
but the drive operates at Fast. So my concern was why it should be
better with a 29160 if the current setup doesn't do Ultra in the first
place. Is there a way to check the cable and the adapter? I trust the
controller, and the drive works at Ultra in a Sun workstation.
With kind regards,
--
Baurzhan Ismagulov
http://www.kz-easy.com/
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