[CentOS] Curious fdisk report on large disk

Tue Apr 26 16:25:42 UTC 2011
James Pearson <james-p at moving-picture.com>

Timothy Murphy wrote:
> I have a 1.5TB internal disk on my server.
> I partitioned this with fdisk,
> and CentOS-5.6 runs perfectly on it.
> But fdisk gives a very strange report.
> 
> Here is the perfectly normal response to mount:
> -----------------------------
> /dev/sdb10 on / type ext3 (rw)
> proc on /proc type proc (rw)
> sysfs on /sys type sysfs (rw)
> devpts on /dev/pts type devpts (rw,gid=5,mode=620)
> /dev/sdb2 on /boot type ext3 (rw)
> tmpfs on /dev/shm type tmpfs (rw)
> /dev/sdb5 on /home type ext3 (rw)
> /dev/sdb6 on /common type ext3 (rw)
> /dev/sdb7 on /BackupPC type ext3 (rw)
> /dev/sdb8 on /Photos type ext3 (rw)
> none on /proc/sys/fs/binfmt_misc type binfmt_misc (rw)
> sunrpc on /var/lib/nfs/rpc_pipefs type rpc_pipefs (rw)
> nfsd on /proc/fs/nfsd type nfsd (rw)
> -----------------------------
> and here is the response to "sudo fdisk /dev/sdb"
> -----------------------------
> Disk /dev/sdb: 1500.3 GB, 1500301910016 bytes
> 255 heads, 63 sectors/track, 182401 cylinders
> Units = cylinders of 16065 * 512 = 8225280 bytes
> 
> This doesn't look like a partition table
> Probably you selected the wrong device.
> 
>    Device Boot      Start         End      Blocks   Id  System
> /dev/sdb1   ?      188019      188051      253319   e4  SpeedStor
> Partition 1 does not end on cylinder boundary.
> /dev/sdb2   ?       62656      186401   993984023   98  Unknown
> Partition 2 does not end on cylinder boundary.
> /dev/sdb3   ?      105611      225119   959953209   7d  Unknown
> Partition 3 does not end on cylinder boundary.
> /dev/sdb4   ?         347         865     4161536    0  Empty
> Partition 4 does not end on cylinder boundary.
> 
> Partition table entries are not in disk order
> -----------------------------

Could it be that the partition table has become corrupt (e.g. overwritten)?

If this has been the case, then you need to find a tool that can attempt 
to recover the partition table - see 
<http://tldp.org/HOWTO/Partition/recovering.html>

James Pearson