View previous topic :: View next topic |
Author |
Message |
tuxp3 n00b
Joined: 28 May 2004 Posts: 61
|
Posted: Thu Sep 23, 2004 4:24 pm Post subject: recover data from a hdd with a bad buffer (cache) |
|
|
Hello,
my friend seems to have somehow got his 20gb hdd fried, but because the cache/buffer (the 2mb one) is the only thing bad, he seems to be able to see the data, but not copy it off of the drive.
If he tryes to copy data off the drive it will transfer 2mb then it will hang and windows will drop the drive.
however i am running linux and i have a spare 20gb and i want to just a sector by sector copy to the 100% good drive
how can i disable dd (or anyother tool) from using the cache/buffer
i looked at the hdparm man pages but nothing actually set or turned off the buffer..
as long as the buffer isnt involved then it will work
Any ideas welcome
also his drive is NTFS
and i recently compiled my kernel for hdd raw innerface |
|
Back to top |
|
|
KingTaco Developer
Joined: 22 Aug 2003 Posts: 207 Location: Bay Area, CA
|
|
Back to top |
|
|
tuxp3 n00b
Joined: 28 May 2004 Posts: 61
|
Posted: Thu Sep 23, 2004 8:06 pm Post subject: hdparm -switchs |
|
|
These are the only revent hdparm switchs i could find...
Quote: |
-A Disable/enable the IDE drive's read-lookahead fea-
ture (usually ON by default).
...
-P Set the maximum sector count for the drive's inter-
nal prefetch mechanism. Not all drives support
this feature.
....
-W
Disable/enable the IDE drive's write-caching feature (default state is undeterminable; manufacturer/model specific).
... OR ...
-r
Get/set read-only flag for device. When set, write operations are not permitted on the device
|
if i set -A disabled and set -P to a very low value 0 or 1 would this minimize the chance of the hdd using the cache when using 'dd' to do a sector by sector copy to the working hdd? also, will this slow things down alot or just a little bit? what are the chances i could get 100% of the data from the drive using this method? what other methods are there ?
Thanks Tux |
|
Back to top |
|
|
tuxp3 n00b
Joined: 28 May 2004 Posts: 61
|
Posted: Fri Sep 24, 2004 10:45 pm Post subject: |
|
|
in case anybody cares.. it worked perfectly i made the drive read-only and disabled the read ahead and used dd if=/dev/hdd of=/dev/hdc -bs 2048 it took 1.5 hours but its worth it
Thanks tux |
|
Back to top |
|
|
|