I've been looking at the Infortrend iSCSI/SATA units, and there's one
glaring aspect: none have dual controllers (for failover).

Is there some fundamental reason for this, perhaps in the nature of iSCSI?

Thanks...

Andrew

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I don't really have an answer for you Andrew, I'm looking for a
clarification to your question.

Are you just looking for a network failover option, or do you want a
"no single point of failure" iSCSI box?

I am sure that I have seen iSCSI boxes with dual netowrk connections
that support failover, but they are not fault tolerant like the FC
storage systems from Engenio and Xyratex are. Is this OK for your
application?

-Jim

Andrew Gideon wrote:
> I've been looking at the Infortrend iSCSI/SATA units, and there's one

> glaring aspect: none have dual controllers (for failover).
>
> Is there some fundamental reason for this, perhaps in the nature of
iSCSI?
>
> Thanks...
>
>         Andrew

[ Post a follow-up to this message ]

jimwall2000@yahoo.com wrote:

> Are you just looking for a network failover option, or do you want a
> "no single point of failure" iSCSI box?

The latter is the "problem".

> I am sure that I have seen iSCSI boxes with dual netowrk connections
> that support failover, but they are not fault tolerant like the FC
> storage systems from Engenio and Xyratex are. Is this OK for your
> application?

Most - if not all - of the devices I've seem (I'm working my way through the
web, I think {8^) have (at least) dual network ports.  I'm looking for 
full
redundancy.

On page on my screen now is:

http://adjile.com/mass.html

They've an iSCSI product (from Adaptec, I believe), but it doesn't appear to
have dual controllers.  Another product on that page (at the top) does have
dual controllers as an option, but it is either FC or SCSI (and also, it
appears, SATA1 drives; at least some Infortrend units appear to use SATA2).

I don't think I've yet to see a dual-controller iSCSI unit.  So I'm
wondering if I've just had bad luck so far, or if there's some reason for
this of which I'm ignorant.

- Andrew

[ Post a follow-up to this message ]

Andrew Gideon wrote:

> I don't think I've yet to see a dual-controller iSCSI unit.  So I'm
> wondering if I've just had bad luck so far, or if there's some reason for
> this of which I'm ignorant.

It was [bad] luck.  Equallogic does this.

- Andrew

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In article <3148768.exFYJbOoZW@no.to.be.used.news.int.tagonline.com>,
Andrew Gideon <cR182Driver45@gideon.org> wrote:

> I've been looking at the Infortrend iSCSI/SATA units, and there's one
> glaring aspect: none have dual controllers (for failover).

There is another: poor tech support. After the company moved, their
director of tech support left the company. The person who took over also
left the company. The tech people they have had there in 2003 were
relatively new to the company and its products, and their staff was
limited. I don't know what their current situation is.

I could also say that at least two units of their older SCSI controllers
worked exceptionally well at garbling all the data on the RAID drives
under their control and erroneously blaming the problem on the drives or
not even being aware there was any problem. That's a small anecdote,
FWIW.

[ Post a follow-up to this message ]

I was looking at NetApp FAS270c recently. They mention Failover capable
but not sure if that means dual controllers. NetApp controller or
'shrunken head' as they call it, ' hosts only single processor (
running Data ONTAP ) along with dual Gb NICs and dual FC ports. It does
not account for 'single point of failure' for controller as such. I am
not sure if another shrunken head is taken on board, will it provide
redundancy.

Pras

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The FAS270c has dual controllers capable of failover and failback. In
normal mode of operation each controller works as an independent unit
but if one of the controllers fail the partner can take over the
responsibilities of the failed controller in a seamless fashion which
is transparent to the host. So it is possible to configure these
systems such that there is no spof.

Vinay

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Hi Andrew
Did you ever find a product that is iSCSI/SATA with dual controllers?
Thanks
Brianne

quote:
Originally posted by Andrew Gideon 
I've been looking at the Infortrend iSCSI/SATA units, and there's one
glaring aspect: none have dual controllers (for failover).

Is there some fundamental reason for this, perhaps in the nature of iSCSI?

Thanks...

Andrew 

[ Post a follow-up to this message ]