On Aug 31, 2009 14:25 -0700, Justin Maggard wrote: > On Aug 31, 2009 13:02 -0400, Ric Wheeler wrote: > > Mount after fsck: > > Aug 31 12:27:12 megadeth kernel: EXT4-fs (dm-75): > > ext4_check_descriptors: Checksum for group 487 failed (59799!=46827) > > Aug 31 12:27:12 megadeth kernel: EXT4-fs (dm-75): group descriptors > > corrupted! > > Ah, so it's not just me. It looks like you're seeing the exact same > thing I reported a few days ago in the ">16TB issues" thread. You > don't even have to do anything fancy to make this happen. My test > case involves simply creating 5 directories on the newly-created > 64-bit filesystem, and running e2fsck on it immediately after > unmounting to get the same results. Justin, could you please replicate this corruption, collecting some additional information before & after. My recollection is that the corruption appears in the first few groups, so 64kB should be plenty to capture the group descriptor tables (where the checksum is kept). - mke2fs - dd if=/dev/XXX bs=4k count=16 | gzip -9 > /tmp/gdt-new.gz - mkdir ... - sync - dd if=/dev/XXX bs=4k count=16 | gzip -9 > /tmp/gdt-mkdir.gz - umount - dd if=/dev/XXX bs=4k count=16 | gzip -9 > /tmp/gdt-umount.gz - e2fsck - dd if=/dev/XXX bs=4k count=16 | gzip -9 > /tmp/gdt-e2fsck.gz Cheers, Andreas -- Andreas Dilger Sr. Staff Engineer, Lustre Group Sun Microsystems of Canada, Inc. -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
