Hi there,
I am having some problems with e2fs utils and was wondering if you could
help clear some things out for me. Please CC me as I am not subscribed to
the list.
I start with a dump of my partition table:
##########################################################################
FDISK
##########################################################################
:# fdisk -l /dev/hdc
Disk /dev/hdc: 255 heads, 63 sectors, 789 cylinders
Units = cylinders of 16065 * 512 bytes
Device Boot Start End Blocks Id System
/dev/hdc1 * 1 399 3204936 b Win95 FAT32
/dev/hdc2 400 529 1044225 e Win95 FAT16 (LBA)
/dev/hdc3 530 659 1044225 83 Linux native
/dev/hdc4 660 789 1044225 83 Linux native
# fdisk -l -u /dev/hdc
Disk /dev/hdc: 255 heads, 63 sectors, 789 cylinders
Units = sectors of 1 * 512 bytes
Device Boot Start End Blocks Id System
/dev/hdc1 * 63 6409934 3204936 b Win95 FAT32
/dev/hdc2 6409935 8498384 1044225 e Win95 FAT16 (LBA)
/dev/hdc3 8498385 10586834 1044225 83 Linux native
/dev/hdc4 10586835 12675284 1044225 83 Linux native
Next, I tried to badblock the partition space before I mke2fs.
2 weird things happened:
1) badblocks kept on trying to access a block beyond the end of the
device/partition (1044226) !! Thank god it wasn't allowed to do it. Below
is the output from the badblocks run and also from my /var/log/messages
2) even though badblocks finished, it never showed me on stdout the
badblock numbers!! I had to rerun with -o badblocks.txt to get the actual
numbers. Is this a bug ?
Now that I think of it a second time, the badblock # was 10440224, which
might mean this: Note the "<----WTF ???" comments. Maybe when it was
printed out on screen, it was written over by the blocks counter (due to
me using the -s switch) and thus I couldn't "see it" on screen.
Does my thinking here make sense?
Should badblocks store the bad blocks until the end of the run if the -s
switch is used ?
##########################################################################
BADBLOCKS
##########################################################################
# badblocks -c64 -svw /dev/hdc3
Checking for bad blocks in read-write mode
>From block 0 to 1044225
Writing pattern 0xaaaaaaaa: done
Reading and comparing: 104422472/ 1044225 <--- WTF ????
done
Writing pattern 0x55555555: done
Reading and comparing: done
Writing pattern 0xffffffff: done
Reading and comparing: done
Writing pattern 0x00000000: done
Reading and comparing: done
Pass completed, 1 bad blocks found.
#at the end of each "Writing pattern 0x...."
Dec 3 20:25:39 kernel: attempt to access beyond end of device
Dec 3 20:25:39 kernel: 16:03: rw=0, want=1044226, limit=1044225
#at the end of each "Reading and comparing: done"
Dec 3 20:28:03 kernel: attempt to access beyond end of device
Dec 3 20:28:03 kernel: 16:03: rw=0, want=1044226, limit=1044225
Well after I was done with badblocks -o I went on to e2fsck with 1024byte
blocks (I am gonna have lots of small files). But that wouldn't fly. The
output below tells why, but I am not sure why it would be having short
reads that early into the partition...
##########################################################################
MKE2FS 1024
##########################################################################
# mke2fs -b 0124 -m 1 /dev/hdc3
Filesystem label=
OS type: Linux
Block size=1024 (log=0)
Fragment size=1024 (log=0)
131072 inodes, 1044225 blocks
10442 blocks (1.00%) reserved for the super user
First data block=1
128 block groups
8192 blocks per group, 8192 fragments per group
1024 inodes per group
Superblock backups stored on blocks:
8193, 24577, 40961, 57345, 73729, 204801, 221185, 401409, 663553,
1024001
Writing inode tables: 0/128^H^H^H^H^H^H^H
Could not write 8 blocks in inode table starting at 8:
Attempt to write block from filesystem resulted in short write
So I tried 2048byte blocks, but I got yet another problem this time! It
ignores the badblock (1044224) saying it's out of range!? (even though the
partition has 1044225 blocks, and even though I never specified the
start/end blocks myself (i let it auto-figure it out)). Any ideas ?
Should my partitions have been even-numbered in block size ? Is this a
kernel problem or an e2fs utils problem (i think the latter)
##########################################################################
MKE2FS 2048
##########################################################################
# mke2fs -c -l /tmp/bad -b 2048 -m 1 /dev/hdc3
mke2fs 1.25 (20-Sep-2001)
Filesystem label=
OS type: Linux
Block size=2048 (log=1)
Fragment size=2048 (log=1)
130560 inodes, 522112 blocks
5221 blocks (1.00%) reserved for the super user
First data block=0
32 block groups
16384 blocks per group, 16384 fragments per group
4080 inodes per group
Superblock backups stored on blocks:
16384, 49152, 81920, 114688, 147456, 409600, 442368
Bad block 1044224 out of range; ignored. <--- WTF ???
Checking for bad blocks (read-only test): done
Writing inode tables: done
Writing superblocks and filesystem accounting information: done
This filesystem will be automatically checked every 38 mounts or
180 days, whichever comes first. Use tune2fs -c or -i to override.
##########################################################################
Any feedback/help would be much appreciated.
Thanks in advance
PS: Please CC me as I am not subscribed to the list.
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On Dec 07, 2001 18:10 +0200, PANTELIS PROIOS wrote:
> I am having some problems with e2fs utils and was wondering if you could
> help clear some things out for me. Please CC me as I am not subscribed to
> the list.
>
> I start with a dump of my partition table:
> ##########################################################################
> FDISK
> ##########################################################################
>
> # fdisk -l -u /dev/hdc
> Disk /dev/hdc: 255 heads, 63 sectors, 789 cylinders
> Units = sectors of 1 * 512 bytes
>
> Device Boot Start End Blocks Id System
> /dev/hdc1 * 63 6409934 3204936 b Win95 FAT32
> /dev/hdc2 6409935 8498384 1044225 e Win95 FAT16 (LBA)
> /dev/hdc3 8498385 10586834 1044225 83 Linux native
> /dev/hdc4 10586835 12675284 1044225 83 Linux native
>
>
> 1) badblocks kept on trying to access a block beyond the end of the
> device/partition (1044226) !! Thank god it wasn't allowed to do it. Below
> is the output from the badblocks run and also from my /var/log/messages
Did you repartition the drive before doing this? If so, you need to
reboot to have the changes take effect (sad, I know).
> # badblocks -c64 -svw /dev/hdc3
>
> Checking for bad blocks in read-write mode
> >From block 0 to 1044225
> Writing pattern 0xaaaaaaaa: done
> Reading and comparing: 104422472/ 1044225 <--- WTF ????
>
> #at the end of each "Writing pattern 0x...."
> Dec 3 20:25:39 kernel: attempt to access beyond end of device
> Dec 3 20:25:39 kernel: 16:03: rw=0, want=1044226, limit=1044225
Hmm, kind of strange that the very last block is "bad". More likely
it is an error somewhere in the partitioning code (or no reboot, as
above) which is reporting the wrong size for the partition. Now that
I think about it, Linux is unable to use the last 512 bytes of any
partition, so it should never tell you that the partition has an odd
number of sectors in it. What does /proc/partitions say?
> Well after I was done with badblocks -o I went on to e2fsck with 1024byte
> blocks (I am gonna have lots of small files). But that wouldn't fly. The
> output below tells why, but I am not sure why it would be having short
> reads that early into the partition...
>
> # mke2fs -b 0124 -m 1 /dev/hdc3
>
> Filesystem label=
> OS type: Linux
> Block size=1024 (log=0)
> Fragment size=1024 (log=0)
> 131072 inodes, 1044225 blocks
^^^^^^^ This is very strange. Above, fdisk says the units
are 512-byte sectors, yet this says 1024-byte blocks?
> Could not write 8 blocks in inode table starting at 8:
> Attempt to write block from filesystem resulted in short write
No idea about this part.
> So I tried 2048byte blocks, but I got yet another problem this time! It
> ignores the badblock (1044224) saying it's out of range!? (even though the
> partition has 1044225 blocks, and even though I never specified the
> start/end blocks myself (i let it auto-figure it out)). Any ideas ?
Probably because mke2fs expects the bad blocks list to be in the same
units as the filesystem blocksize. If you created the bad blocks list
with a 1024-byte blocksize, it will not work with a 2048-byte filesystem.
You need to divide all the block numbers by 2. So, no real bug here.
Cheers, Andreas
--
Andreas Dilger
http://sourceforge.net/projects/ext2resize/
http://www-mddsp.enel.ucalgary.ca/People/adilger/