Re: Raid 5 question, need help

[Les Connor [SBS MVP]]

I imagine this box is still under warranty? Even if not, you need to call
Dell.

There have been several issues with 2900 firmware for raid, backplane, and
HDD's. I've seen this on a number of 29xx servers in the past year, and it's
always been resolved - quickly - by calling Dell support, running a few
tests, and downloading and updating firmware. The support has been really
good.

--
Les Connor [SBS MVP]
________________________
Get the SBS BPA here:
http://support.microsoft.com/kb/940439/en-us

"Eric" <Er...@discussions.microsoft.com> wrote in message
news:1ABF13D8-A853-4D0B...@microsoft.com...
> Hi all,
> PE2900 use PERC 5/i control 5 sas HD, RAID 5. The raid utility menu show
> “VD
> count 1, PD count 4”, after troubleshooting the PD count show 3 & 1
> missing
> on the utility menu, (but system is running ok).
> Q 1. 5 HD is good for raid 5? If yes how to design the 5 HD for raid.
> Q 2. Disk space 73G x5 x75% must be 273GB, now only 202 left, why?
> Q 3. The HD light is on for all disk. but only 3 HD keep blinking. The
> non-blinking HD mean’s dead?
> Thanks for all help…
> Eric
>
>
>

[Holz]

On Tue, 19 Feb 2008 10:54:01 -0800
Eric <Er...@discussions.microsoft.com> wrote:

> Hi all,
> PE2900 use PERC 5/i control 5 sas HD, RAID 5. The raid utility menu
> show “VD count 1, PD count 4”, after troubleshooting the PD count
> show 3 & 1 missing on the utility menu, (but system is running ok).
> Q 1. 5 HD is good for raid 5? If yes how to design the 5 HD for raid.
> Q 2. Disk space 73G x5 x75% must be 273GB, now only 202 left, why?
> Q 3. The HD light is on for all disk. but only 3 HD keep blinking.
> The non-blinking HD mean’s dead?
> Thanks for all help…
> Eric
>
>
>

Just as Les said, do not be tempted to do anything, call DELL. Their
support is solid from what I have seen so far.

--
live, or leave & let live.
:-)

[Leythos]

In article <1ABF13D8-A853-4D0B...@microsoft.com>,
Er...@discussions.microsoft.com says...
> Hi all,
> PE2900 use PERC 5/i control 5 sas HD, RAID 5. The raid utility menu show ?VD
> count 1, PD count 4?, after troubleshooting the PD count show 3 & 1 missing

> on the utility menu, (but system is running ok).
> Q 1. 5 HD is good for raid 5? If yes how to design the 5 HD for raid.
> Q 2. Disk space 73G x5 x75% must be 273GB, now only 202 left, why?
> Q 3. The HD light is on for all disk. but only 3 HD keep blinking. The

> non-blinking HD mean?s dead?
> Thanks for all help?
> Eric

I'm not sure what you're saying above...

You have 5 drives, all SAS, in a RAID-5 solution

You have 1 Virtual Disk, it's your RAID array.

You have a PD count (Physical Disk) count of 4 drives

You now mention that some troubleshooting, but you don't say why...

You say PD count shows 3 and 1 missing, which indicates that you have 1
drive that has failed, possibly removed from the system. This needs to
be fixed immediately or you could lose the entire server/data.

You said you have 5 drives, but the PD count shows 4, which seems to
indicate you don't have 5 drives, or you have a Hot-Spare that is not
being shown in the PD count for the array.

Either way, you need to contact an IT person or Dell and get them to
help you NOW, before you have another fault.

--

Leythos
- Igitur qui desiderat pacem, praeparet bellum.
- Calling an illegal alien an "undocumented worker" is like calling a
drug dealer an "unlicensed pharmacist"
spam9...@rrohio.com (remove 999 for proper email address)

[Eric]

Yes my system use raid5 + Hot-Spare.
Thanks all, I already call dell, hope can fix asap.
Eric

[Leythos]

In article <F35242CE-D491-4600...@microsoft.com>,
Er...@discussions.microsoft.com says...

> Yes my system use raid5 + Hot-Spare.
> Thanks all, I already call dell, hope can fix asap.

If the system has a real hot spare then the 5th drive, the spare, would
automatically swap itself into the failed position, you should be able
to ident the drive - flashing light on front of it, while in the BIOS or
it may also be a different color illumination, indicating which drive is
actually failed.

[Eric]

Hi Leythos,
now system running ok, just space is different before (It's confused), How
do i know the hot-spare disk is ok & working, because the light not blinking
when disk is write & read the data.
Thank for the help..

[Les Connor [SBS MVP]]

Use the Dell Openmanage Server Administrator application that shipped with
the server. You can manage the raid from there, including get status of
disks/drives, blink, etc.

--
Les Connor [SBS MVP]
________________________
Get the SBS BPA here:
http://support.microsoft.com/kb/940439/en-us

"Eric" <Er...@discussions.microsoft.com> wrote in message

news:AA5DB639-BCC3-41B2...@microsoft.com...

[Eric]

I just download & install the openmanager (dell support ask for install), but
I never use this utility, Is raid management will demage the current data?
Thanks for help.

[SuperGumby [SBS MVP]]

I would not have installed OM had it not been previously on the box. I
concede that Dell have asked you to do this.

Tell all workstations to shut down. Shutdown and restart the SBS. Go into
BIOS (system level 1st, then RAID BIOS). How many drives are detected? How
many in System BIOS vs RAID BIOS?

I'm using onboard(card assisted, PE840) PERC 5i and it has four channels,
you cannot connect 5 HDD's to it (AFAIK, can't check right now the system is
10 mile away). The standalone PERC 5i PCIe card has 8 channels.

Open the box. Are all 5 HDD's connected to something? Are they connected to
the same thing or does one connect 'somewhere else'?

"Eric" <Er...@discussions.microsoft.com> wrote in message

news:93715DBE-5E29-4C49...@microsoft.com...

[Eric]

show 3 online and 1 missing (0 missing and 1,2,3 online), b4 show 4 online
(0,1,2,3.)
thanks for help..

[SuperGumby [SBS MVP]]

OK, so where is your 5th HDD?
Do you have a 5th HDD? (open the box, look)

Some of the comments have been specifically caused by 'Disk space 73G x5
x75% must be 273GB, now only 202 left, why?', indicating you think the
system has 5 HDD's, but making a mistake in calculation.

The general equation for RAID 5 capacity is (N-1). The Number of drives - 1
used for parity (parity is actually distributed but let's keep it simple).
A 4 HDD RAID 5 gives 3*N usable space (sortta equivalent to your 75%
suggestion).
A 5 HDD RAID 5 gives 4*N usable space (80%).

Given 4 HDD's I would more likely do 3 in RAID 5 (66% usable) and a
hotspare, total 50% usable.

It sounds more like you have 4 HDD's in RAID5 with no hotspare, giving 3*73
(or about 200GB) usable.

"Eric" <Er...@discussions.microsoft.com> wrote in message

news:E292CE49-C8EE-4CC6...@microsoft.com...

[SuperGumby [SBS MVP]]

sorry, most of those N's should be C's (Capacity).

"SuperGumby [SBS MVP]" <n...@your.nellie> wrote in message
news:OUcHNM3...@TK2MSFTNGP02.phx.gbl...

[Eric]

5 slot each slot with HD , right now the size is 202g(around) ,each HD can
use 67G so 67 x4 x0.75 =201g, the size is right for 4 HD, but I remember
before it was around 280G, so it's confusing me.

--Eric

[SuperGumby [SBS MVP]]

Why are you multiplying C (capacity) by (N-1) (Number of disks in array - 1)
by .75 (some number drawn out of a hat)?

Look through my posts. Answer the specific questions.

"Eric" <Er...@discussions.microsoft.com> wrote in message

news:FE054569-C9C5-49FE...@microsoft.com...