[opensuse] Can not mount 'special' dvd.
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-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Hi, I was trying an experiment. First, I created an vfat filesystem as an image on a file: # dd if=/dev/zero of=dvd.vfat.image bs=32K count=143433 # losetup /dev/loop7 dvd.vfat.image # mkdosfs -n "Backup" -m boot_message /dev/loop7 mkdosfs 2.11 (12 Mar 2005) Loop device does not match a floppy size, using default hd params # file -s /dev/loop7 /dev/loop7: x86 boot sector, mkdosfs boot message display # nimrodel:/Grande/imgs # losetup -d /dev/loop7 /etc/fstab: /imgs/dvd.vfat.image /mnt/dvd.vfat.img vfat noauto,loop,fmask=0117,dmask=0007 0 0 And with this, I can do "mount /mnt/dvd.vfat.img" and the filesystem is mounted, I can copy files to it, etc. It works. Then, I umount it, and burn the image to a DVD (it has the exact size). I byte compare the DVD to its source image on the HD, and its matches. So far, so good. I have the appropriate entry in fstab to mount the dvd (of any type): /dev/hdc /mnt/dvd auto ro,noauto,user,exec 0 0 The DVD reads correctly - apparently: # file -s /dev/hdc /dev/hdc: x86 boot sector, mkdosfs boot message display But it does not mount: # mount /mnt/dvd mount: /dev/hdc: can't read superblock And the kernel log says only this: Mar 8 21:47:53 nimrodel kernel: FAT: logical sector size too small for device (logical sector size = 512) Why can't I mount it? The funny thing, is that I create encrypted vfat images, burn them to dvd, and they mount fine. But not a plain image! Did I do something wrong? Perhaps I used the wrong options to mkdosfs? - -- Cheers, Carlos E. R. -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.9 (GNU/Linux) iEYEARECAAYFAkm0NTEACgkQtTMYHG2NR9WE8QCdGbMru/C+9IIkctvHPxPDY3Vt sdMAmwdlwJ9C18UwcPEK8Gz5h2YqqlAl =VoAg -----END PGP SIGNATURE----- -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
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Carlos E. R. wrote:
But it does not mount:
# mount /mnt/dvd mount: /dev/hdc: can't read superblock
And the kernel log says only this:
Mar 8 21:47:53 nimrodel kernel: FAT: logical sector size too small for device (logical sector size = 512)
What about specifying -t vfat in the fstab? Does that help? -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
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-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On Sunday, 2009-03-08 at 14:42 -0700, John Andersen wrote:
What about specifying -t vfat in the fstab? Does that help?
Same thing. I tried via command line: nimrodel:~ # mount -v -t vfat /dev/dvd /mnt/dvd mount: /dev/hdc: can't read superblock Mar 9 00:21:25 nimrodel kernel: FAT: logical sector size too small for device (logical sector size = 512) I'm starting to think it must be the sector size indeed, it does not match the media... maybe when the disk is encrypted there is a layer in between and the layer that mounts vfat does not sees the wrong sector size, and that is why it works. I should then use this in mkdosfs: -S logical-sector-size Specify the number of bytes per logical sector. Must be a power of 2 and greater than or equal to 512, i.e. 512, 1024, 2048, 4096, 8192, 16384, or 32768. But which record size for dvds? I think it is 32 KiB, but I'm not sure. [...] No, it does not accept 32KiB: nimrodel:/imgs # nice mkdosfs -v -n "MediaBackup" -m boot_message -S 8192 /dev/loop7 mkdosfs 2.11 (12 Mar 2005) Loop device does not match a floppy size, using default hd params Auto-selecting FAT32 for large filesystem /dev/loop7 has 64 heads and 32 sectors per track, logical sector size is 8192, using 0xf8 media descriptor, with 573732 sectors; file system has 2 32-bit FATs and 8 sectors per cluster. FAT size is 36 sectors, and provides 71703 clusters. Volume ID is 49b4575b, volume label MediaBackup. nimrodel:/imgs # nice mkdosfs -v -n "MediaBackup" -m boot_message -S 16384 /dev/loop7 mkdosfs 2.11 (12 Mar 2005) Loop device does not match a floppy size, using default hd params Auto-selecting FAT32 for large filesystem mkdosfs: Attempting to create a too large file system Even 8KiB is not mountable as image: nimrodel:/imgs # losetup /dev/loop7 dvd.vfat.image nimrodel:/imgs # fsck /dev/loop7 fsck 1.40.8 (13-Mar-2008) dosfsck 2.11, 12 Mar 2005, FAT32, LFN /dev/loop7: 1 files, 1/71703 clusters nimrodel:/imgs # losetup -d /dev/loop7 nimrodel:/Grande/imgs # mount /mnt/dvd.vfat.img mount: wrong fs type, bad option, bad superblock on /dev/loop7, missing codepage or helper program, or other error In some cases useful info is found in syslog - try dmesg | tail or so Mar 9 00:47:12 nimrodel kernel: FAT: bogus logical sector size 8192 Mar 9 00:47:12 nimrodel kernel: VFS: Can't find a valid FAT filesystem on dev loop7. With 4 KiB or 2 KiB it is mountable as image. I'll try to burn that and see what happens. - -- Cheers, Carlos E. R. -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.9 (GNU/Linux) iEYEARECAAYFAkm0Zq0ACgkQtTMYHG2NR9UmQQCdGVrSc6+GFxnf/fzd8S39ZWTB /FYAn34BMviGQKMb5w9hPeJbhx6/pQ7/ =2Pyp -----END PGP SIGNATURE----- -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
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-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On Monday, 2009-03-09 at 01:45 +0100, Carlos E. R. wrote:
But which record size for dvds? I think it is 32 KiB, but I'm not sure. .. With 4 KiB or 2 KiB it is mountable as image. I'll try to burn that and see what happens.
The 2 KiB logical sector size did the trick. I had seen, using "/usr/bin/dvd+rw-mediainfo /dev/dvd" this output: READ TRACK INFORMATION[#1]: Track State: complete Track Start Address: 0*2KB Free Blocks: 0*2KB Track Size: 2295104*2KB So, seeing the "2KB" in there, I thought that would be the sector size. Using that in mkdosfs produced an image that worked when burned to a DVD. So, I can now burn DVDs as FAT instead of ISO. Now, the next step would be to see if my windows friends can read it or not. I'm curious O:-) - -- Cheers, Carlos E. R. -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.9 (GNU/Linux) iEYEARECAAYFAkm0fFwACgkQtTMYHG2NR9WARACeOWX9jdvPkxz4pFKWPYGG1shX Q/wAnihec7Pkk2QSq0lNIuFNqj8vpfa+ =YDpG -----END PGP SIGNATURE----- -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
participants (3)
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Carlos E. R.
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Carlos E. R.
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John Andersen