On Sunday 08 May 2005 16:13, Tom wrote:
>
Hi, Tom.

>      I posted here the day the torrents were available, 1 ->
> checked, but the CD6 iso failed.  So I got the separate torrent for
> CD5-6, and that CD6 iso checked.  

I took the Silver 5-6 torrent, and it's that one that is failing.  Is the one 
you got different?

> IIRC, shortly after Warly posted 
> (on cooker) that the mini CD and CD6 (0f 1-6) would fail md5sum, but
> still be usable.  I believe the problem was a fairly obscure md raid
> (win-fake-raid) module that was missing from the torrents. CD6 isn't
> all that important anyhow.
>
Fair enough.  I could probably ignore it, then.

>      As to 'md5sum /dev/hdd'.  Well you already know my disdain for
> GUI frontends to cdrecord (particularly k3b), but I an others have
> posted many times that -dao _must_ be used, -pad or -data should
> _never_ be used for iso's. 

Somehow I have not managed to catch that in the past, but point taken, and 
I'll remember it.

> An that best results will probly come 
> from 1/3 speed.  Speed being the lessor of your burners rating, or
> the media used.  So for the best drives and Cdr's, that means no
> faster than 16x.
>
I am burning at 1/3 speed - 8x on a 24x drive.

>       If 'md5sum /dev/hdd' results in an I/O error, it usually means
> the drive being used to read, can't read the CDr correctly.  Just as
> often a hardware or media problem than an improperly burned iso. Is
> hdd your burner?, or a CDrom?  

hdd is the burner.

> The burner used to make the CD should 
> be able to read it better than a cdrom drive can.  'Course if you're
> makin CD's to be used on other systems, they will need to be able to
> be read by CDrom drives.  CD-RW's use a "tighter" an brighter laser
> than CD (CDrom or DVDrom) drives do.
>
>      So it's better to use a CDrom drive to check the md5sum. If the
> first try returns I/O error, try several more times.  It might help
> to close the console being used, remove an re-insert the Cdr, an
> then try again with a new console.  If many tries fail, you can
> always try 'dd'ing the CDr to a file on your hardrive an then md5sum
> that. But IME, if you can't check the CDr, then the dd'd iso probly
> won't check either.
>
>      One last note; if you happen to be usin a LE2005 system (or
> older Mandrake with a recent kernel) to make the CD's, burning
> should be done as root. cdrecord as user is denied access (recent
> kernel security changes) to:
>
> cdrecord: Operation not permitted. WARNING: Cannot set RR-scheduler
> cdrecord: Permission denied. WARNING: Cannot set priority using
> setpriority().
> cdrecord: WARNING: This causes a high risk for buffer underruns.
>
>      While burning as user is still possible (the above are just
> warnings, not errors) the resulting CD's can be harder to read.
> Specially at the very outer edges.  CDr's record from the inside
> near the spindle to the outer rim.  While the md5sum may fail, it
> could be that only the last file recorded is corrupt. The CD should
> most likely still be usable.
>
>     If you still have problems, I'd be interested in the hardware
> you're using, uname -r, 

uname -r
2.6.8.1-24W4L

> the result of an -atip on the media being 
> used, 

I don't understand that one, Tom.  I presume -atip is a switch - on which 
command?

> and if a simple 'cdrecord -v -eject speed=4 dev=ATA:X,Y,Z -dao 
> xxxxxx.iso',  still produces an uncheckable md5sum CDr.

OK - I'll try that one last test, but don't I somewhere have to tell it the 
device name?

Anne
-- 
Registered Linux User No.293302 (http://counter.li.org/)
Have you visited http://twiki.mdklinuxfaq.org yet?  Mandrake at all levels

Attachment: pgpW5vmJUUJ5o.pgp
Description: PGP signature

Reply via email to