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On Fri, 2004-10-01 at 00:49, Marcin Gibuła wrote: > > Volume6 is a two partition concatenated volume mad up of partitions sda4 > > (109GiB) and sda2 (32kiB!) (in this order!) on the disk you sent me the > > ldm dump from. You should assemble this as described for Volume2 and > > then mount the created MD device with the ntfs driver. > > Maybe I should explain what is my disc layout... > Volume2 is one partition, and Volume6 is mounted as one of its directories, > something like: > > D:\ <- Volume2 > D:\download <- Volume6 > > Volume6 works fine without using software raid though. Volume2 does not. I would not advise you to use volume6 without the md driver. You are then missing the last 32kb off the end and you never know when they might be needed and access to the volume might fall over just when you expect it least. Also the backup bootsector is in the last sector so you are at present missing that and even worse something like chkdsk could think "corrupt volume, lets fix it" and damage your volume because you are missing the end. > > Let me know how it goes. Both success and failures are interesting to > > me as I do not remember anyone actually having had spanned ldm volumes > > before so it would be nice to know it all works... > > I've tried the following: > > # mdadm --build /dev/md1 -l linear -n 2 /dev/sda1 /dev/sda3 > mdadm: array /dev/md1 built and started. > # mount /dev/md1 /mnt/d Volume2 not working can have a possible explanation in that it might be assembled incorrectly. For example, Windows is using 512-byte blocks but Linux 1024-byte blocks so if your first partition has an odd number of sectors Windows will use the last sector whereas Linux will cut off the last sector and hence all data in the second partition will be shifted by 512-bytes in the array which you cause all data to appear corrupt in the second part of the volume. I have seen this happen in my own experiments on the Windows NT4 fault tolerant linear raid volumes, I have not done experiments with Windows 2k/xp LDM linear raid volumes. If this is the case you cannot use the md driver and are stuck I am afraid. At least I am not aware of any Linux utility/driver that will allow you to work in this case. Alternatively maybe Windows 2k/XP LDM linear raid volumes are using the cluster size as the block size instead of 512-byte blocks. If that were the case and your cluster size is > 1024 bytes (very likely on such a large volume, it is probably 4096 bytes) then the second part of the volume is again misaligned when assembled but in the opposite direction. Fortunately you can fix this case by using the "--rounding=" parameter to mdadm. So if you have a cluster size of 4k try --rounding=4. (If you don't know your cluster size enable debugging in the ntfs driver and then do the mount and "dmesg | grep cluster_size" will tell you the answer. To enable debugging in the driver it must be compiled with debugging enabled and you need to, as root, do: "echo 1 > /proc/sys/fs/ntfs-debug" after loading the module if modular and before doing the mount command.) # ls /mnt/d > ls: reading directory /mnt/d: Input/output error > > dmesg output: > NTFS volume version 3.1. > NTFS-fs error (device md1): ntfs_readdir(): Actual VCN (0x6e68dc76fa7923) of > index buffer is different from expected VCN (0x4). Directory inode 0x5 is > corrupt or driver bug. I have seen this particular error before and it was due to the volume having been upgraded from FAT to NTFS (and the conversion utility apparently had screwed up the vcns in at least one directory). Running "chkdsk /f" on it fixed it in that particular case (even though chkdsk reported no errors, apparently it fixed them without telling anyone!). So this is worth trying before you start messing around with --rounding= and mdadm. Best regards, Anton -- Anton Altaparmakov <aia21 at cam.ac.uk> (replace at with @) Unix Support, Computing Service, University of Cambridge, CB2 3QH, UK Linux NTFS maintainer / IRC: #ntfs on irc.freenode.net WWW: http://linux-ntfs.sf.net/, http://www-stu.christs.cam.ac.uk/~aia21/ - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/ | ||||||||||
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