What am I doing wrong ??? Or is Adaptec 21610SA just a crappy RAID card ?

On Fri, 03 Dec 2004 09:34:20 -0500, Nik Simpson
wrote:

flux wrote:


In an ordinary office environment, how would backups get accomplished if
the computers are running 24/7?

So your experience of normal office environments is clearly limited if
you don't understand that systems stay on even during backup, shock
horror, pictures at 10.

What? Really? Haven't you switched to using "power-free" backup yet?

Malc.

In comp.sys.ibm.pc.hardware.storage Anton Rang wrote:
flux writes:
In article , Anton Rang
wrote:

SATA disks typically have less error checking internally than SCSI,

How do you know this?

*points out the window to the Seagate office down the road*

I work in storage; I talk with drive engineers (and RAID engineers).

It is also not really surprising, given that SATA is ATA with
better cabeling and a better command-set, but not better drive
hardware or electronics. (I think there is no need to explain why
SCSI is a different quality and performance level than ATA...)

Though sometimes SCSI is not better: I still remember when a lot of
SCSI disk in Suns failed because Quantum had just packed a SCSI
interface on an EIDE disk.

Arno
--
For email address: lastname AT tik DOT ee DOT ethz DOT ch
GnuPG: ID:1E25338F FP:0C30 5782 9D93 F785 E79C 0296 797F 6B50 1E25 338F
"The more corrupt the state, the more numerous the laws" - Tacitus

In article ,
Malcolm Weir wrote:

Well, my beliefs are based on experience and direct conversations with
disk drive manufacturers.

What are yours based on?


Ditto.

A logical rebuttal might be that manufacturers could offer lifetime
warranties on SCSI drives because they are just that durable, but a
warranty that long doesn't make sense from a marketing point of view
because the manufacturers do want their customers to upgrade eventually.

You call *that* "logical"?

yes.

Figures.

It isn't.


Drives have a service life which is related to the MTBF, but is
different from it.

Here's a scenario that is, hopefully, simple enough even for you:

Taking your 1.2Mhour MTBF, that might mean:

Year 1: 1 out of every 150 drives fails. 95% of failed drives get
returned for replacement. Cost of replacement = 100% cost of new
drive.
Year 2: 1 out of every 146 drives fails. 90% of failed drives get
returned for replacement. Cost of replacement = 90% cost of new
drive.
Year 3: 1 out of every 142 drives fails. 85% get returned. Cost of
replacement = 80% cost of new drive.
Year 4: 1 out of every 135 drives fails. 75% get returned. Cost of
replacement = 60% of cost of new drive.
Year 5: 1 out of every 100 drives fails. 50% get returned. Cost of
replacement = 40% of cost of new drive.
Year 6: No one cares. 0% get returned. Cost of replacement n/a.

So my point is logical after all.


No, they probably upgrade.

Or.... can't find the paperwork/remember that they have a warranty...

Don't mean "and"?

But wait didn't someone just say the cost of
upgrading is peanuts compared to the cost of downtime.

Yes, it is. Welcome to the point. I hope you'll be very happy
together.

So doesn't that make your argument circular?

flux wrote:

In article ,
Malcolm Weir wrote:

Now, has it dawned on you that even the most rudimentary of network
servers has multiple NICs? Why do you think that is? Are server
manufacturers silly?

That's a very recent developlment.

Nonsense. I was building Novell servers in 1992 with 3 NICs in them.

In computing terms, it's ancient technology.

Odie
--

RetroData
Data Recovery Experts
www.retrodata.co.uk

In article ,
Malcolm Weir wrote:

On Fri, 03 Dec 2004 07:14:51 GMT, flux wrote:

In article ,
Malcolm Weir wrote:

Now, has it dawned on you that even the most rudimentary of network
servers has multiple NICs? Why do you think that is? Are server
manufacturers silly?

That's a very recent developlment. Even gigabit is relatively recent.

1999.

Must mean that everyone now has 10G Ethernet at the desktop.

Where *hard* problems are, at least for those of us in
comp.arch.storage, it is assumed that the network problem is already
solved. Need 10GB/sec of network bandwidth and don't have a 10G
Ethernet? Simply trunk 10 1000BaseT nets to your switch! Cisco (and
the like) can handle that part of the problem.

Again, this sounds very rare.

Yet it isn't. Gosh. Could it be that you are ignorant of what you
write?

Ditto.

In article ,
Malcolm Weir wrote:

How is three years any signficantly less costly than two?

Did you flunk elementary math?

Here's the answer:

In a 6 year period, how often will you have to replace the disks if
you it:

(a) Every two years?
(b) Every three years?

This is significant?

Arno Wagner wrote:

In comp.sys.ibm.pc.hardware.storage Anton Rang wrote:
flux writes:
In article , Anton Rang
wrote:

SATA disks typically have less error checking internally than SCSI,

How do you know this?

*points out the window to the Seagate office down the road*

I work in storage; I talk with drive engineers (and RAID engineers).

It is also not really surprising, given that SATA is ATA with
better cabeling and a better command-set, but not better drive
hardware or electronics.

Unless it it does have better drive hardware and electronics. There is no
PATA Raptor.

(I think there is no need to explain why
SCSI is a different quality and performance level than ATA...)

Because the drive manufacturers decided they wanted it that way. That's the
_only_ reason. Western Digital has decided that they _don't_ want it that
way.

Though sometimes SCSI is not better: I still remember when a lot of
SCSI disk in Suns failed because Quantum had just packed a SCSI
interface on an EIDE disk.

You mean that the disk had a SCSI-to-EIDE bridge on it? Or do you just mean
that Quantum was making bargain-basement SCSI disks using some of the same
components that they used in their consumer line?

You really have to stop confusing the interface with the quality level.
There is no inherent relationship between them. Historically IDE drives
have been built to a lower quality level than SCSI drives. If the drive
manufactures had wanted to position SCSI as the consumer product and IDE as
the enterprise product then you would be complaining about putting IDE
interfaces on cheap SCSI drives instead.

Arno

--
--John
Reply to jclarke at ae tee tee global dot net
(was jclarke at eye bee em dot net)

In article , flux
writes

Must mean that everyone now has 10G Ethernet at the desktop.

Come on. The context of the discussion is network servers.

--
..sigmonster on vacation

Malcolm Weir wrote:
On Fri, 03 Dec 2004 07:19:38 GMT, flux wrote:


In article ,
"Nik Simpson" wrote:


But they are basing their warranty calculations on how the drive is used,
and (with the exception of WD's 10K drives) they expect them to go into PC
devices which don't run 24x7, so the MTBF is expected to be stretched
because the drive is spending a good deal of its time doing very little or
powered down.

The Tivo I have attached to my TV streams video to disk 24/7. That's a
consumer appliance!


Yes. What's your point?

Do you think that *every* Tivo does that?



To be fair, yes, that's pretty much standard operating procedure for a
TIVO, both mine are on UPS and never (well almost never) go down. That
said...

1. TIVO doesn't give you a 5-year warranty on the drive, they give you
one year warranty.

2. By far the most common failure mode for TIVO is hard drive death, and
it typically occurs outside warranty.

So using TIVO as an example doesn't really help his case.

--
Nik Simpson

In comp.sys.ibm.pc.hardware.storage J. Clarke wrote:
Arno Wagner wrote:

In comp.sys.ibm.pc.hardware.storage Anton Rang wrote:
flux writes:
In article , Anton Rang
wrote:

SATA disks typically have less error checking internally than SCSI,

How do you know this?

*points out the window to the Seagate office down the road*

I work in storage; I talk with drive engineers (and RAID engineers).

It is also not really surprising, given that SATA is ATA with
better cabeling and a better command-set, but not better drive
hardware or electronics.

Unless it it does have better drive hardware and electronics. There is no
PATA Raptor.

Of course.

(I think there is no need to explain why
SCSI is a different quality and performance level than ATA...)

Because the drive manufacturers decided they wanted it that way. That's the
_only_ reason. Western Digital has decided that they _don't_ want it that
way.

Not quite. If you look at the systems, SCSI is a far more mature and
versatile interface with a far better command set. (S)ATA is still
behind. Given the two interfaces it is really quite obvious which to use
in high-quality drives and which to use in low quality ones. Also
remember that you can put 7/15 targets on an SCSI bus but 1/2 on an
(S)ATA bus. It is quite clear which one you want in a high-priced
server. I am not saying that it could not be done the other way round,
but it is far mor logical the way it is.

Though sometimes SCSI is not better: I still remember when a lot of
SCSI disk in Suns failed because Quantum had just packed a SCSI
interface on an EIDE disk.

You mean that the disk had a SCSI-to-EIDE bridge on it? Or do you just mean
that Quantum was making bargain-basement SCSI disks using some of the same
components that they used in their consumer line?

Actually I think it had a bridge on it. It was a bit slower than the
corresponding IDE model which is a hint in that direction. At that time
there was no IDE in Sun workstations, maybe that was the main
reson for this model. I remember that many of these drives failed
within a year and had to be replaced. (Being run 24/7 in the workstations
of course. Seems somebody did not thke _that_ into account...)

You really have to stop confusing the interface with the quality level.

I don't confuse them. However it is a good first indicator, if the
price is also significanlty different. Of course the correct
thing to do is have a look into the datasheet before deciding
on a drive.

There is no inherent relationship between them. Historically IDE drives
have been built to a lower quality level than SCSI drives. If the drive
manufactures had wanted to position SCSI as the consumer product and IDE as
the enterprise product then you would be complaining about putting IDE
interfaces on cheap SCSI drives instead.

Perfectly true. SCSI does not guarantee higher quelity for exactly
the reason you state. It is only a first indicator.

Arno
--
For email address: lastname AT tik DOT ee DOT ethz DOT ch
GnuPG: ID:1E25338F FP:0C30 5782 9D93 F785 E79C 0296 797F 6B50 1E25 338F
"The more corrupt the state, the more numerous the laws" - Tacitus