S
Skybuck Flying
Hello,
This night I was trying to backup my source code, emails, websites and
information to a DVD.
This time I wanted to make 100% sure that every bit was verified and tested.
Out of 5 DVD's WinRar reported 4 DVD's as bad/corrupted/crc32 errors !
Only one DVD came through 100% perfect as far as I can tell... another DVD
came very close 99.999999% perfect... but still an unexplained and
undetected bit error somewhere... only the DVD copieing program detected
it... I want to be 100% sure so this second one doesn't count.
That's a failure rate of 80% !
I tried the following:
1. Burning at 4 MByte/Sec.
2. Burning at 12 MByte/Sec.
3. Burning at 16 MByte/Sec.
4. Blowing the drive clean a little bit.
5. Lowering the fans on the PC case... this seemed to help a little bit or
maybe it was a fluck of luck... this DVD was 100% ok ?!?
6. Listening on the table to see if under neighbours or cars/trucks driving
by where making noise.
I noticed the IBM/Hitachi Harddisk do make quite some noise/vibrations on
the wooden table.
7. Disconnected internet.
Maybe harddisk/filesystem a little bit fragmented... by the buffers seemed
to remain full... the read buffer in nero remained above 90% full...
The dvd burner (benq) did seem to drop to 23% at occasions.
One dvd had a little bit of crease and had the most errors. (Wrote with
waterpen on it before burning the rest after).
All other dvd's came clean out of the sony cakebox.
I feel lucky and blessed that I at least got one good DVD out of this
experiment and necessary backup.
Let this posting be a warning message to those programmers and other people
out there thinking about using DVD's as backup mediums !
Always verify the DVD... but that's not enough !
One DVD still came through "verified" by the DVD writing program... however
WinRar still reported corruption.
Another explanation could be that some of my RAM chips might be
corrupted/defect... however shouldn't I have noticed that by now ?!?
I also tried extracting the originals on the harddisk... and no bit errors
or crc's error happen there which more or less proves that it's probably not
a memory error... since it would probably use the same ammount of memory and
such.
I am just hoping that one copy remains good fingers crossed... I also had
another copy... at least the rar's where good.. but maybe some of the
software like executables for extraction might be nuked.
(I also have dual layer verbatims on my closest shelfes... didn't try those
yet... since backup data was about 2.7 GB... so saving those for some other
time
... these were 4 GB Sony DVD's which I used...)
What's your experience with burning DVD's... anybody out there experiencing
high failure rates ?!?
Maybe with sony dvd's or benq dvd drives ?
(This is 2006 technology )
Bye,
Skybuck.
This night I was trying to backup my source code, emails, websites and
information to a DVD.
This time I wanted to make 100% sure that every bit was verified and tested.
Out of 5 DVD's WinRar reported 4 DVD's as bad/corrupted/crc32 errors !
Only one DVD came through 100% perfect as far as I can tell... another DVD
came very close 99.999999% perfect... but still an unexplained and
undetected bit error somewhere... only the DVD copieing program detected
it... I want to be 100% sure so this second one doesn't count.
That's a failure rate of 80% !
I tried the following:
1. Burning at 4 MByte/Sec.
2. Burning at 12 MByte/Sec.
3. Burning at 16 MByte/Sec.
4. Blowing the drive clean a little bit.
5. Lowering the fans on the PC case... this seemed to help a little bit or
maybe it was a fluck of luck... this DVD was 100% ok ?!?
6. Listening on the table to see if under neighbours or cars/trucks driving
by where making noise.
I noticed the IBM/Hitachi Harddisk do make quite some noise/vibrations on
the wooden table.
7. Disconnected internet.
Maybe harddisk/filesystem a little bit fragmented... by the buffers seemed
to remain full... the read buffer in nero remained above 90% full...
The dvd burner (benq) did seem to drop to 23% at occasions.
One dvd had a little bit of crease and had the most errors. (Wrote with
waterpen on it before burning the rest after).
All other dvd's came clean out of the sony cakebox.
I feel lucky and blessed that I at least got one good DVD out of this
experiment and necessary backup.
Let this posting be a warning message to those programmers and other people
out there thinking about using DVD's as backup mediums !
Always verify the DVD... but that's not enough !
One DVD still came through "verified" by the DVD writing program... however
WinRar still reported corruption.
Another explanation could be that some of my RAM chips might be
corrupted/defect... however shouldn't I have noticed that by now ?!?
I also tried extracting the originals on the harddisk... and no bit errors
or crc's error happen there which more or less proves that it's probably not
a memory error... since it would probably use the same ammount of memory and
such.
I am just hoping that one copy remains good fingers crossed... I also had
another copy... at least the rar's where good.. but maybe some of the
software like executables for extraction might be nuked.
(I also have dual layer verbatims on my closest shelfes... didn't try those
yet... since backup data was about 2.7 GB... so saving those for some other
time
... these were 4 GB Sony DVD's which I used...)What's your experience with burning DVD's... anybody out there experiencing
high failure rates ?!?
Maybe with sony dvd's or benq dvd drives ?
(This is 2006 technology
)Bye,
Skybuck.
