1Mini-Howto for verifying a selfmade CD
2
31) verifying the data layer
4
5	To verify if all data on the disk can be read,
6	use SCSI verify. This can be done with the
7	sformat utility.
8
9	use: sformat -verify [target] [lun] [scsibus]
10
11	If the CD-R device is connected to target 2 on SCSI bus 0
12	sformat -verify 2  0
13
14	sformat can be found on ftp://ftp.berlios.de/pub/sformat
15
16	NOTE: Not all CD-ROm drives support verifying
17	NOTE: All TAO tracks end in 2 unreadable run-out sectors
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192) verifying the filesystem layer
20
21	A quick check is to mount the CD and to use star to read
22	all files on the filesystem.
23
24	mount -r /dev/cdrom /cdrom      (modify for your OS)
25	cd /cdrom
26	star -cPM . >/dev/null
27
28	If no errors can be found, all files are readable.
29
30	star can be found on ftp://ftp.berlios.de/pub/star
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32
33	You also may want to compare the filesystem on the CD
34	with the original data. This can be done with star too.
35
36
37	(cd /master_for_cd; star -cPM .)|(cd /cdrom; star -diff -v)
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392a) verifying the iso image before creating the CD
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41	You may check the filesystem image by mounting it with my
42	"fbk" on Solaris or the loopback driver on Linux.
43
44	On Linux type:
45		mount isoimage.raw -r -t iso9660 -o loop /mnt
46
47	On SunOS type:
48		mount -r -F fbk -o type=hsfs /dev/fbk0:isoimage.raw /mnt
49
50For Solaris 8 and later you may also use the Sun lofi driver (see README.sun-lofi)
51
52	The check the filesystem with:
53
54		(cd /master_for_cd; star -cPM .)|(cd /mnt; star -diff -v)
55
56
57Solaris has a bug with hardlinks. It generates different inode numbers
58for the hardlinks to a file. This makes it impossible for star to
59check hard links. Use
60
61(cd /master_for_cd; star -cPM .)|(cd /cdrom; star -diff -v diffopts=!hardlink)
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63in this case.
64
65NOTE: Some operating systems have a read ahead bug that causes I/O errors for
66the last file(s) on a CD. This seems at least to be true for all Linux versions
67and for Solaris 7 FCS. For Solaris 7 there is a patch (107465-02) that you should
68install. This I/O error problem does not occur with DAO disks and with TAO disks
69that have been written with wodim -pad.
70
71Joerg Schilling
72
73Source: README.verify from cdrtools package
74Edited for cdrkit by Christian Fromme <kaner@strace.org> and Eduard Bloch
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76