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Date: Sun, 16 Nov 2014 14:25:51 -0500
Message-ID: <CACpH0MdejdpsNW=CwutjvZfyM+SdB5fBBzu7WAdT55mD1pdG_A@mail.gmail.com>
Subject: Re: OT-ish SATA port replicators vs. SAS "expanders"
From: Zaphod Beeblebrox <zbeeble@gmail.com>
To: Darren Pilgrim <list_freebsd@bluerosetech.com>
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On Sat, Nov 15, 2014 at 9:08 PM, Darren Pilgrim <
list_freebsd@bluerosetech.com> wrote:


> A SATA port replicator (or port multiplier) is more like a USB hub: you
> plug the replicator into a host SATA port and it provides more than one
> SATA port for devices.  I've yet to see one without interoperability
> problems.  They also add a big risk: if one of the devices on a replicator
> has a problem, the host can't reset individual replicated ports--just the
> host port.
>
>
I have used the Mediasonic 'Probox' 4 drive eSATA for some years.  I have 6
of them now.  If you were running a standard RAID, you'd have the problem
that one drive can take down the array and that you'd have huge trouble
recovering.  However, ZFS handles this well...