Sudden power loss causes damage?

Are modern hard disk drives susceptible to hardware damage or data
corruption from sudden power loss?

By "sudden power loss", I mean like if you pull the power supply plug
out off the wall socket, or if the hard disk drive power cable is
disconnected.

Partly curious. Thank you.

Modern journalling file system are sufficiently robust against power loss,
but any unwritten DATA may be lost, causing corruption in the user's files
structure.

Don't take chances and buy an UPS.

"John Doe" wrote in message
...
Are modern hard disk drives susceptible to hardware damage or data
corruption from sudden power loss?

By "sudden power loss", I mean like if you pull the power supply plug
out off the wall socket, or if the hard disk drive power cable is
disconnected.

Partly curious. Thank you.

If the drive is writing, the current sector will be bad. Documented in many
drive manuals, and also the servo chipset docs.

The drive will always retract the heads to landing zone or offload ramp.

"John Doe" wrote in message
...
Are modern hard disk drives susceptible to hardware damage or data
corruption from sudden power loss?

By "sudden power loss", I mean like if you pull the power supply plug
out off the wall socket, or if the hard disk drive power cable is
disconnected.

John Doe wrote in
message ...

Are modern hard disk drives susceptible to hardware
damage or data corruption from sudden power loss?

Nope, they should all handle that with no data loss or damage.

By "sudden power loss", I mean like if you pull the power supply plug
out off the wall socket, or if the hard disk drive power cable is
disconnected.

Partly curious. Thank you.

You know what that did to the cat dont you ?

Previously John Doe wrote:
Are modern hard disk drives susceptible to hardware damage or data
corruption from sudden power loss?

By "sudden power loss", I mean like if you pull the power supply plug
out off the wall socket, or if the hard disk drive power cable is
disconnected.

Partly curious. Thank you.

There was a time where certain drives suffered bad sectors when
this happens. The problem should be solved now.

Writing a sector takes something like 10-20 us. The drive buffer
capacitor should have enough power to keep the electronics working
that long. The disk will detect the power-fail a bit before
it has problems with the voltage levels.

If you short out the power leads, it may be a different story.

Arno
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"Arno Wagner" wrote in message
...

Writing a sector takes something like 10-20 us. The drive buffer
capacitor should have enough power to keep the electronics working
that long. The disk will detect the power-fail a bit before
it has problems with the voltage levels.

Delusional nonsense. Ronnie also claimed that. Manuals say otherwise.

There is a chipset doc online that says low voltage simply disables the write
head.

Alexander Grigoriev wrote:
Modern journalling file system are sufficiently robust against power loss,
but any unwritten DATA may be lost, causing corruption in the user's files
structure.

I think that's expressed poorly, because I can interpret it to be either
true or a mis-statement. Vague terms include "unwritten" and "user's
file structure."

A Google of "two phase commitment" might be relevant.

Don't take chances and buy an UPS.

"John Doe" wrote in message
...

Are modern hard disk drives susceptible to hardware damage or data
corruption from sudden power loss?

By "sudden power loss", I mean like if you pull the power supply plug
out off the wall socket, or if the hard disk drive power cable is
disconnected.

Partly curious. Thank you.





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minimize spam. Our true address is of the form .

"Eric Gisin" wrote:
"Arno Wagner" wrote

Writing a sector takes something like 10-20 us. The drive buffer
capacitor should have enough power to keep the electronics
working that long. The disk will detect the power-fail a bit
before it has problems with the voltage levels.

Delusional nonsense. Ronnie also claimed that. Manuals say
otherwise.

There is a chipset doc online that says low voltage simply disables
the write head.

Instead of a troll, why don't you post a link to that chipset dock.







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From: "Eric Gisin"
From: "Eric Gisin" ericgisin @hotmail.com
Newsgroups: comp.sys.ibm.pc.hardware.storage
Subject: Sudden power loss causes damage?
Date: Wed, 2 Feb 2005 14:34:04 -0800
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"John Doe" wrote in message
...
"Eric Gisin" wrote:
"Arno Wagner" wrote

Writing a sector takes something like 10-20 us. The drive buffer
capacitor should have enough power to keep the electronics
working that long. The disk will detect the power-fail a bit
before it has problems with the voltage levels.

Delusional nonsense. Ronnie also claimed that. Manuals say
otherwise.

There is a chipset doc online that says low voltage simply disables
the write head.

Instead of a troll, why don't you post a link to that chipset dock.

The title is Texas Instruments Servo/MSC Product Line User's Guide (PDF).
This is over 5 years old, so things may have changed.

You are better of reading hard drive manuals. IBM's describe the "at most one
bad sector" behavior.

Arnie's "drive buffer capacitor" is a fabrication. You cannot store enough
energy on those dinky caps.

After 10 us, 100 uF, 1A, the voltage drops by 100 mV. 100 uF is not a
terribly big capacitor.

"Eric Gisin" wrote in message
...
"John Doe" wrote in message
...
"Eric Gisin" wrote:
"Arno Wagner" wrote

Writing a sector takes something like 10-20 us. The drive buffer
capacitor should have enough power to keep the electronics
working that long. The disk will detect the power-fail a bit
before it has problems with the voltage levels.

Delusional nonsense. Ronnie also claimed that. Manuals say
otherwise.

There is a chipset doc online that says low voltage simply disables
the write head.

Instead of a troll, why don't you post a link to that chipset dock.

The title is Texas Instruments Servo/MSC Product Line User's Guide (PDF).
This is over 5 years old, so things may have changed.

You are better of reading hard drive manuals. IBM's describe the "at most
one
bad sector" behavior.

Arnie's "drive buffer capacitor" is a fabrication. You cannot store enough
energy on those dinky caps.