Storage Spaces: Dual Redunancy?

I am trying to read
https://technet.microsoft.com/en-us/...(v=ws.11).aspx

Under "Resilient storage", I see

"Mirror. Writes data in a stripe across multiple disks while also
writing one or two extra copies of the data. Use the mirror layout for
most workloads – it helps protect your data from disk failures and
provides great performance, especially when you add some SSDs to your
storage pool and use storage tiers."

Is this telling me what I hope it is: that I could set up a Storage
Space across a dozen or so drives and have up to two drives fail without
losing data?
--
Pete Cresswell

On Fri, 21 Oct 2016 21:31:03 -0400, "(PeteCresswell)"
wrote:

I am trying to read
https://technet.microsoft.com/en-us/...(v=ws.11).aspx

Under "Resilient storage", I see

"Mirror. Writes data in a stripe across multiple disks while also
writing one or two extra copies of the data. Use the mirror layout for
most workloads – it helps protect your data from disk failures and
provides great performance, especially when you add some SSDs to your
storage pool and use storage tiers."

Is this telling me what I hope it is: that I could set up a Storage
Space across a dozen or so drives and have up to two drives fail without
losing data?

If that's what you're after, why not just use FlexRaid or SnapRaid? They
do the same thing.

Per Char Jackson:
If that's what you're after, why not just use FlexRaid or SnapRaid? They
do the same thing.

I am currently using DriveBender. It got really flaky some months ago,
so I re-built the system and changed over to an enclosure with
backplanes and changed from multiple SATA cards to a single SAS card.

So far, so good.... And the ability to yank a drive, put it in another
machine, and have access to whatever files are on the drive has a
certain appeal to me..... but I'm on my guard now and evaluating various
alternatives if this build starts getting weird on me.

My ignorance is huge in this area. Stumbled on Storage Spaces when
trying to Google for alternatives....


Now that you have mentioned them, I need to look into FlexRaid and
SnapRaid. The appeal there would be the possibility that I could
implement one of them without rebuilding the existing Windows
7/purchasing Windows 8.

Assuming both will run under Windows-7, do you prefer one over the
other?
--
Pete Cresswell

On Sat, 22 Oct 2016 10:27:18 -0400, "(PeteCresswell)"
wrote:

Per Char Jackson:
If that's what you're after, why not just use FlexRaid or SnapRaid? They
do the same thing.

Now that you have mentioned them, I need to look into FlexRaid and
SnapRaid. The appeal there would be the possibility that I could
implement one of them without rebuilding the existing Windows
7/purchasing Windows 8.

Right, at least for SnapRaid. I'm less familiar with the underpinnings
of FlexRaid but I think it's true there, as well.

Assuming both will run under Windows-7, do you prefer one over the
other?

I'm not using either of them, but I'm most interested in SnapRaid
because its limited feature set doesn't overlap with DB. You can specify
one or more drives to be your parity drives, with the only big
requirement being that parity drives have to be as big as your biggest
data drive, and you can decide how many drive failures you want to guard
against by designating that number of parity drives.

The two strikes against SnapRaid that I have a

1) I wouldn't want to run it against the DB volume directly, but rather
against the individual drives that make up the DB volume. I assume that
means that the individual drives need to have a drive letter assigned,
which I don't normally do. This would apply equally to FlexRaid.

2) SnapRaid uses the snapshot model, so every night or so you'd run it
and have it update the parity drives. If you lose one or more drives, up
to the number of parity drives, you can recover to the state of the last
snapshot.

By contrast, I believe FlexRaid has a real-time capability, so that the
parity drives are kept updated at all times. FlexRaid isn't free,
though, and when I was more serious about it (2010 timeframe?) the
author was prone to disappearing for months at a time.

Both packages had good reviews, so it's mostly laziness that has kept me
from taking the next step and picking one. It's 5-6 years later now, and
I wonder if both are still being developed and supported.

On Fri, 21 Oct 2016 21:31:03 -0400, "(PeteCresswell)"
wrote:

I am trying to read
https://technet.microsoft.com/en-us/...(v=ws.11).aspx

Under "Resilient storage", I see

"Mirror. Writes data in a stripe across multiple disks while also
writing one or two extra copies of the data. Use the mirror layout for
most workloads – it helps protect your data from disk failures and
provides great performance, especially when you add some SSDs to your
storage pool and use storage tiers."

Is this telling me what I hope it is: that I could set up a Storage
Space across a dozen or so drives and have up to two drives fail without
losing data?

The mainframe computers I maintained had a resilient disc system like
that. It never went wrong. That was about 20 years ago.

Steve

--
Neural Network Software for Windows http://www.npsnn.com

On 10/21/2016 9:31 PM, (PeteCresswell) wrote:
I am trying to read
https://technet.microsoft.com/en-us/...(v=ws.11).aspx

Under "Resilient storage", I see

"Mirror. Writes data in a stripe across multiple disks while also
writing one or two extra copies of the data. Use the mirror layout for
most workloads – it helps protect your data from disk failures and
provides great performance, especially when you add some SSDs to your
storage pool and use storage tiers."

Is this telling me what I hope it is: that I could set up a Storage
Space across a dozen or so drives and have up to two drives fail without
losing data?

Would this be the same as what we use to call it when we partitioned a
disk. As I read it they are mirroring disk partition 1 (C) to disk
partition 2 (D).

With the size of disk today that would be a very affective way use of
the disk.

I have a 2TB disk on my desktop and a 500GB disk on my laptop that is
synchronized to the desktop. I am using about 100GB of space on my
laptop, so would have the same on the Desktop or about 100GB out on 2 TB
of storage space,