CD-Prüfen mit readcd
In der letzten Charge grml-CDs, die ich von meinem Bruder bedruckt bekommen habe, haben sich ein paar kaputte CDs reingeschlichen. Beim Booten der grml-CD bekommt man dann meistens SquashFS-Fehler und “dann geht nix mehr”. Um jetzt die schlechten von den guten[tm] CDs auszusortieren, habe ich readcd verwendet. So schaut das aus wenn es in Ordnung ist:
# readcd -c2scan dev=/dev/cdrom Read speed: 4234 kB/s (CD 24x, DVD 3x). Write speed: 4234 kB/s (CD 24x, DVD 3x). Capacity: 353867 Blocks = 707734 kBytes = 691 MBytes = 724 prMB Sectorsize: 2048 Bytes Copy from SCSI (0,0,0) disk to file '/dev/null' end: 353867 addr: 353867 cnt: 38 Time total: 519.971sec Read 914386.80 kB at 1758.5 kB/sec. Total of 0 hard read errors. C2 errors total: 0 bytes in 0 sectors on disk C2 errors rate: 0.000000% C2 errors on worst sector: 0, sectors with 100+ C2 errors: 0 #
Und die CD schmeisst man lieber weg, wenn man sowas zu sehen bekommt:
Read speed: 4234 kB/s (CD 24x, DVD 3x). Write speed: 4234 kB/s (CD 24x, DVD 3x). Capacity: 353869 Blocks = 707738 kBytes = 691 MBytes = 724 prMB Sectorsize: 2048 Bytes Copy from SCSI (0,0,0) disk to file '/dev/null' end: 353869 readcd: Success. read_cd: scsi sendcmd: no error CDB: BE 00 00 05 66 25 00 00 28 FA 00 00 status: 0x2 (CHECK CONDITION) Sense Bytes: F0 00 25 00 05 66 4B 0A 00 00 21 00 64 00 00 00 Sense Key: 0x5 Illegal Request, Segment 0 Sense Code: 0x64 Qual 0x00 (illegal mode for this track) Fru 0x0 Sense flags: Blk 353867 (valid) illegal block length resid: 105840 cmd finished after 0.030s timeout 40s readcd: Success. Cannot read source disk readcd: Retrying from sector 353829. ....................................... readcd: Success. Error on sector 353867 not corrected. Total of 1 errors. readcd: -noerror set, continuing ... . readcd: Success. Error on sector 353868 not corrected. Total of 2 errors. readcd: -noerror set, continuing ... C2 in sector: 353868 first at byte: 374 (0x02) total: 172 errors addr: 353869 Time total: 594.388sec Read 914391.97 kB at 1538.4 kB/sec. Max corected retry count was 0 (limited to 10). The following 2 sector(s) could not be read correctly: 353867 353868 Total of 2 hard read errors. C2 errors total: 172 bytes in 1 sectors on disk C2 errors rate: 0.000021% C2 errors on worst sector: 172, sectors with 100+ C2 errors: 1