Huge wrote:
> On 2007-09-27, Dave <sorry-no-email@nowhere.com> wrote:
>
>>I'm thinking of buying a used Blade 2000. I've been offered a Dell 147
>>GB F-CAL (fibre) disk. Are Suns fussy about their disks, or will pretty
>>much any FCAL disk work in a Blade 2000?
>>
>>I know on the older machines, it rarely seems to matter who makes the
>>SCSI disk. One usually has to label non-Sun disks, but that is about it.
>>But I've not no idea if this freedom extends to fibre disks.
>
>
> W-e-e-e-e-e-e-e-e-e-e-e-llll. This is long, but bear with me...
>
> I bought a SB2000 a couple of months ago, from eBay, after my main home machine
> (an Ultra 60) died in a lightning strike. (Trying to claim on the insurance for
> a non-PC, non-Mac computer was amusing, but that's another story). The SB2000
> has twin 73GB disks, 4 GB of memory and twin 1.2GHz processors and initially I
> was delighted with it.
>
> I reinstalled everything, restored from the U60 backup tapes and was poised on
> brink of getting disk mirroring set up (which I'd put off, because it's fiddly
> to do and the sort of thing I only do rarely (the systems I work on at work are
> set up by other people)) when it started crashing. No errors, nothing in syslog,
> it just died. I dd'd /home to the other disk to save my work. Then I noticed I
> was getting UFS log rollover errors from the boot disk - they weren't getting
> syslogged, just coming on the console, so I never saw them unless I was actually
> there. After a day of crashes of increasing frequency, it would no longer boot
> from the main disk. Booting from DVD, the main disk could no longer be seen by
> the system at all. probe-scsi also couldn't see it at all.
>
> So I contacted the supplier, who was absolutely brilliant throughout, and he
> sent me another 73Gb disk. This is where it gets relevant to you. The original
> disks were Sun badged ones. The replacement disk was a Fujitsu one. The original
> disk was c1t1d0, the new one came up as c1t33d0, and I *could* *not* make its
> logical ID correct (and no-one responded when I posted here asking for help -
> not to worry, I learned loads about luxadm, OBP, FC-AL disks and so on). I
> decided to press ahead regardless and run the machine with c1t33d0 and c1t2d0,
> but first I ran a surface analysis on the new disk. Hundreds of errors, where it
> said that the error was repairable, but was unable to determine the block ID to
> repair it.
>
> I contacted the supplier again, and he sent me another new disk, only this time
> another Sun badged one, identical to the original. This came up as c1t1d0
> immediately, surface analysis ran fine, so I installed it. By this time, I'd
> reinstalled everything (again) on c1t2d0, so I just made c1t1d0 the mirror. It's
> been absolutely fine for about 10 days now. (I do need to swap the boot disk
> back to c1t1d0, I suppose).
>
> So ... my conclusion? I'd be inclined to think that the SB2000 *is* picky about
> disks, and if I ever need to fit another, I shall be choosy about what I buy.
> Would I ever buy another machine with FC-AL disks? Probably not.
>
> Oh, and "Dear Mr. Sun", what's the point in fitting hot swappable disks to a
> machine with a power supply interlock on its access panel, so you can't open it
> up "hot" to swap the disks anyway?
>
>

Just guessing but it might have something to do with buying disks in
quantity and/or not needing to stock hundreds of different replacement
disks.

On Sep 27, 6:37 am, Dave <sorry-no-em...@nowhere.com> wrote:
> I'm thinking of buying a used Blade 2000. I've been offered a Dell 147
> GB F-CAL (fibre) disk. Are Suns fussy about their disks, or will pretty
> much any FCAL disk work in a Blade 2000?
>
> I know on the older machines, it rarely seems to matter who makes the
> SCSI disk. One usually has to label non-Sun disks, but that is about it.
> But I've not no idea if this freedom extends to fibre disks.

YMMV as they say. Huge had problems with one disk whereas I have 50
odd
of them and nary a squawk from one in the last X # of years. Lest we
forget SAN
used to be exclusively (pretty much ) FC/AL. Anyway - that said all my
disks
are Sun branded. And each one has the latest firmware updates.. How
would you,
if you had to, update a Dell disk? Further I have used lots of SCSI
too and the
non Sun ones did on occasion act strangely. Some died the death. All
the
Sun ones still live : > Recently I purchased an HBA for my 2000. Too
bad the PCI
only has one 66 MHz slot as I built an external 500 GB SATA-II drive
and
it works very well and was under 200 CDN dollars. Fast even at half
speed.
The 2000 with dual 1.2's is a fine box. I dont think they have
released anything to
replace it YET thats worth buying new or used. Still waiting.

In comp.sys.sun.admin Huge <Huge@nowhere.much.invalid> wrote:
> So ... my conclusion? I'd be inclined to think that the SB2000 *is* picky
> about disks, and if I ever need to fit another, I shall be choosy about
> what I buy. Would I ever buy another machine with FC-AL disks? Probably not.

Not my experience. I recently put "defective" disks from an EMC
Symmetrix DMX2 into my SB1000 and had no issues at all.

These are Seagate disks with a custom EMC firmware (they identify themselves
as SX3146707 instead of ST3146707). The two 146GB disks replaced the
original 36GB disks.

--
Daniel

Daniel Rock wrote:
> In comp.sys.sun.admin Huge <Huge@nowhere.much.invalid> wrote:
>
>>So ... my conclusion? I'd be inclined to think that the SB2000 *is* picky
>>about disks, and if I ever need to fit another, I shall be choosy about
>>what I buy. Would I ever buy another machine with FC-AL disks? Probably not.
>
>
> Not my experience. I recently put "defective" disks from an EMC
> Symmetrix DMX2 into my SB1000 and had no issues at all.
>
> These are Seagate disks with a custom EMC firmware (they identify themselves
> as SX3146707 instead of ST3146707). The two 146GB disks replaced the
> original 36GB disks.
>

If EMC thinks they are defective they MIGHT be OK. EMC tends to be
ultra conservative; I worked with an EMC 3630 for several years without
a single failure! Every once in a while someone from EMC would show up
and replace a cable or a circuit board but this was almost always done
without down time! What they replaced was working but they considered
the replacement to be "better" or "more reliable". If it's not the most
reliable storage on the planet, it comes close! If it's not the most
expensive storage on the planet, it comes close!

It's worth noting that there is almost NO secondary market in EMC
equipment; if you didn't buy it from EMC, they won't support it!

Daniel Rock wrote:
> In comp.sys.sun.admin Cydrome Leader <presence@mungepanix.com> wrote:
>> If my display has two pixels, and I know one is broken to start with, yes,
>> I replace it.
>
> Do you replace your car if you jump-started it once?

If my car doesn't work reliably, I find out what's wrong and fix or
replace it. If the disk is purely scratch storage and I wouldn't miss
what's on it, the I would reuse the disk. I however would not store
anything critical on the disk even if it is part of a mirror set.

If your car's steering failed once, would you keep on driving it?

In comp.sys.sun.hardware Daniel Rock <v200740@deadcafe.de> wrote:
> In comp.sys.sun.admin Cydrome Leader <presence@mungepanix.com> wrote:
>> If my display has two pixels, and I know one is broken to start with, yes,
>> I replace it.
>
> Do you replace your car if you jump-started it once?

I would replace what was broken or failing.

I prefer preventative maintenance, not cleaning up larger messes later.

In comp.sys.sun.admin Cydrome Leader <presence@mungepanix.com> wrote:
> I prefer preventative maintenance, not cleaning up larger messes later.

A few "metattach" or "metareplace" are a larger mess?

--
Daniel

In comp.sys.sun.hardware Daniel Rock <v200740@deadcafe.de> wrote:
> In comp.sys.sun.admin Cydrome Leader <presence@mungepanix.com> wrote:
>> I prefer preventative maintenance, not cleaning up larger messes later.
>
> A few "metattach" or "metareplace" are a larger mess?

I guess if you're bored and have nothing better to do with a computer than
stuff it full of blatantly broken drives from a junk pile, then rebuild
the data you're just going to lose anyways next week, because you're
probably also using RAM that's "mostly" OK and SCSI card that "sort of
works" on a system board that's "almost always fine" with power supplies
with fans that "usually" spin, then go for it.

Some people have slightly different standards, and know that drives don't
fix themselves, and always just get worse and should be replaced at the
first signs of trouble, at your convenience, not when they finally do
catastrophically fail.

In comp.sys.sun.admin Cydrome Leader <presence@mungepanix.com> wrote:
> In comp.sys.sun.hardware Daniel Rock <v200740@deadcafe.de> wrote:
>> In comp.sys.sun.admin Cydrome Leader <presence@mungepanix.com> wrote:
>>> I prefer preventative maintenance, not cleaning up larger messes later.
>>
>> A few "metattach" or "metareplace" are a larger mess?
>
> Some people have slightly different standards, and know that drives don't
> fix themselves, and always just get worse and should be replaced at the
> first signs of trouble, at your convenience, not when they finally do
> catastrophically fail.

Do you just replace a flat tire or the entire car?


Let's calculate the probability of a total failure...

Normal SCSI drives have a AFR of ~3%. Let's say the AFR of these drives
is 10 times higher (i.e. 30%). Let's also assume it takes on average 48 hours
to replace a broken drive.

What is the probability that two drives fail within 48 hours?

The probability is ~0.05% p.a. (0.3 * 0.3 * (2/365))


BTW this is the SMART output of one of the drives:

Device: SEAGATE SX3146807FC Version: D010
Device type: disk
Transport protocol: Fibre channel (FCP-2)
Device supports SMART and is Enabled
Temperature Warning Disabled or Not Supported
SMART Health Status: OK

Elements in grown defect list: 8
Vendor (Seagate) cache information
Blocks sent to initiator = 323870666916662
Vendor (Seagate/Hitachi) factory information
number of hours powered up = 27478.45
number of minutes until next internal SMART test = 10

Daniel Rock wrote:
> <snip>
>
> Let's calculate the probability of a total failure...
>
> Normal SCSI drives have a AFR of ~3%. Let's say the AFR of these drives
> is 10 times higher (i.e. 30%). Let's also assume it takes on average 48 hours
> to replace a broken drive.
>
> What is the probability that two drives fail within 48 hours?
>
> The probability is ~0.05% p.a. (0.3 * 0.3 * (2/365))

You've assumed that drives fail independently of each other. If the
drives have a higher probability of failure following some event (e.g.,
a power cycle), then your calculation is flawed. Take another example;
the drive has a 30% chance of not spinning up after a power cycle. The
probability of a catastrophic failure is
0.3 * 0.3 * P(power cycle)
Since you know you will power cycle at some point, you have a 9% chance
of losing your data at that point. Not a risk I'd take.