From mboxrd@z Thu Jan  1 00:00:00 1970
Date: Fri,  4 Sep 2009 13:24:35 +0100
From: Eris Discordia <eris.discordia@gmail.com>
To: Fans of the OS Plan 9 from Bell Labs <9fans@9fans.net>
Message-ID: <F06E182D40A3A51484ADCFA7@[192.168.1.2]>
In-Reply-To: <0a2891b0ca461335221f7788685fca19@quanstro.net>
References: <0a2891b0ca461335221f7788685fca19@quanstro.net>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii; format=flowed
Content-Transfer-Encoding: 7bit
Content-Disposition: inline
Subject: Re: [9fans] Petabytes on a budget: JBODs + Linux + JFS
Topicbox-Message-UUID: 640f0356-ead5-11e9-9d60-3106f5b1d025

> - a hot swap case with ses-2 lights so the tech doesn't
> grab the wrong drive,

This caught my attention and you are the storage expert here. Is there an
equivalent technology on SATA disks for controlling enclosure facilities?
(Other than SMART, I mean, which seems to be only for monitoring and not
for control.)

I have this SATA backplan-inside-enclosure with 3x Barracuda 7200 series 1
TB disks attached. The enclosure lights for the two 7200.11's respond the
right way but the one that's ought to represent the 7200.12 freaks out
(goes multi-color). Have you experienced anything similar? The tech at the
enclosure vendor tells me some Seagate disks don't support control of
enclosure lights.

--On Thursday, September 03, 2009 21:20 -0400 erik quanstrom
<quanstro@quanstro.net> wrote:

> On Thu Sep  3 20:53:13 EDT 2009, rvs@sun.com wrote:
>> "None of those technologies [NFS, iSCSI, FC] scales as cheaply,
>> reliably, goes as big, nor can be managed as easily as stand-alone pods
>> with their own IP address waiting for requests on HTTPS."
>>    http://blog.backblaze.com/2009/09/01/petabytes-on-a-budget-how-to-bui
>>    ld-cheap-cloud-storage/
>>
>> Apart from the obvious comment that I swear I used a quote like that
>> to justify 9P more than once, I'm very curious to know how Plan9
>> would perform on such a box.
>>
>> Erik, do you have any comments?
>
> i'm speaking for myself, and not for anybody else here.
> i do work for coraid, and i do do what i believe.  so
> cavet emptor.
>
> i think coraid's cost/petabyte is pretty competitive.
> they sell 48TB 3u unit for about 20% more.  though
> one could not build 1 of these machines since the
> case is not commercially available.
>
> i see some warning signs about this setup.  it stands
> out to me that they use desktop-class drives and the
> drives appear hard to swap out.  the bandwith out
> of the box is 125MB/s max.
>
> aside from that, here's what i see as what you get for
> that extra 20%:
> - fully-supported firmware,
> - full-bandwith to the disk  (no port multpliers)
> - double the network bandwidth
> - ecc memory,
> - a hot swap case with ses-2 lights so the tech doesn't
> grab the wrong drive,
>
> oh, and the coraid unit works with plan 9.  :-)
>
> - erik
>