Sorry for all the typos. I try to run directly on the system console to avoid creating a coaster if SSH decides to hang up. As a result, I couldn't copy-n-paste exactly what happened. I did take pictures on my phone, but apparently didn't copy to the email very well :-( But many thanks for your help.
On Wed, Jun 29, 2022 at 4:44 AM Thomas Schmitt <[email protected]> wrote: > Hi, > > First of all: Congrats to the success and thanks for the report. > > I have some comments and corrections for the list archive, though: > > Paul von Behren wrote: > > using xorrisofs, copied the ISO using scp to a Ubuntu system > > with the SATA burner, where I used xorisso-as cdrecord.--for_backup > > --for_backup has to be used with xorrisofs (the -as mkisofs emulation), > not with xorrecord (the -as cdrecord emulation). > Its purpose is to put an array of MD5 sums to the end of the ISO 9660 > filesystem and to add an attribute to each data file which points to > their respective MD5 entry in the array. > > Actually xorrecord would refuse on this option: > xorriso : FAILURE : -as cdrskin: Unknown option '--for_backup' > so i assume that you did it right. > > If MD5s were recorded then the -for_backup -check_media run should report > MD5 related messages, like: > > xorriso : UPDATE : Found matching MD5 superblock tag: start=32 size=18 > ... > xorriso : UPDATE : Found matching MD5 tree tag: start=32 size=9022 > ... > xorriso : UPDATE : Found matching MD5 session tag: start=32 size=1969789 > > and at the end of the run > > MD5 checks : lba , size , result > MD5 tag range: 32 , 1969789 , + md5_match > > (With multi-session media there are such lines for each session.) > > > > I then used xoriso check_media_r ... to verify the md5s - all were > > good RC=0. > > The proposed xorriso commands are -check_media and -check_md5_r. > > There is no -check_media_r. xorriso would refuse: > xorriso : FAILURE : Not a known command: '-check_media_r' > > > > I read a paper that studied failures of burns at various speeds. Even if > the > > drive vendor said the drive supported 4x (or faster), the study found > much > > fewer failures at slower speed (1x). > > My own experience is that healthy drives on healthy media can reliably > write at the maximum speed which they promise. But a BD drive at 10x speed > is a frightening experience. > > I have a Pioneer BDR-S09 which rotates so fast when reading BD-RE that > newer Verbatim BD-RE physically break by getting cracks at the rim of > their inner hole. When the crack reaches the dye, the medium becomes > unreadable. > he drive does not react on read speed settings. So the only way to slow > it down is to curb the willingness of xorriso to take data as fast as > the drive delivers them. Therefore i use this xorriso speed setting > command when checkreading BD media by the Pioneer BDR-S09: > -read_speed soft_force:6xBD > "soft_force:" is quite new. Only the recent version 1.5.4 supports it. > > > Have a nice day :) > > Thomas > >
