GPT partition table? how to remove it,

[vaclinux]

Dear guys,
i have screwed my external slim hard disk, the partition table is changed to be GPT,

sudo fdisk /dev/sdb

Output :

WARNING: GPT (GUID Partition Table) detected on '/dev/sdb'! The util fdisk doesn't support GPT. Use GNU Parted.


Disk /dev/sdb: 320.0 GB, 320072933376 bytes
255 heads, 63 sectors/track, 38913 cylinders, total 625142448 sectors
Units = sectors of 1 * 512 = 512 bytes
Disk identifier: 0xa37a2115

Device Boot Start End Blocks Id System
/dev/sdb1 * 63 307243124 153621531 7 HPFS/NTFS
/dev/sdb2 307243125 414027179 53392027+ 7 HPFS/NTFS
/dev/sdb3 414027180 524297339 55135080 7 HPFS/NTFS
/dev/sdb4 524297340 625137344 50420002+ 83 Linux

there is some tips that i have tried,
like run gparted
sudo parted /dev/sdb
Output: (Sorry,Output's quite long error,)

GNU Parted 1.8.8
Using /dev/sdb
Welcome to GNU Parted! Type 'help' to view a list of commands.
(parted) rescue
Warning: /dev/sdb contains GPT signatures, indicating that it has a GPT table.
However, it does not have a valid fake msdos partition table, as it should.
Perhaps it was corrupted -- possibly by a program that doesn't understand GPT
partition tables. Or perhaps you deleted the GPT table, and are now using an
msdos partition table. Is this a GPT partition table?
*** glibc detected *** parted: double free or corruption (!prev): 0x00000000010cd490 ***
======= Backtrace: =========
/lib64/libc.so.6[0x3c9da77ec8]
/lib64/libc.so.6(cfree+0x76)[0x3c9da7a486]
/lib64/libparted-1.8.so.8[0x3650a4077f]
/lib64/libparted-1.8.so.8[0x3650a414e3]
/lib64/libparted-1.8.so.8(ped_disk_new+0x9a)[0x3650a15aea]
parted[0x40656a]
parted(interactive_mode+0xfc)[0x40d50c]
parted(main+0x8f)[0x40a7cf]
/lib64/libc.so.6(__libc_start_main+0xe6)[0x3c9da1e576]
parted[0x405349]
======= Memory map: ========
00110000-0012b000 r-xp 00000000 08:01 120224 /lib64/libselinux.so.1
0012b000-0032a000 ---p 0001b000 08:01 120224 /lib64/libselinux.so.1
0032a000-0032b000 r--p 0001a000 08:01 120224 /lib64/libselinux.so.1
0032b000-0032c000 rw-p 0001b000 08:01 120224 /lib64/libselinux.so.1
0032c000-0032d000 rw-p 0032c000 00:00 0
00400000-00414000 r-xp 00000000 08:01 32823 /sbin/parted
00613000-00614000 rw-p 00013000 08:01 32823 /sbin/parted
00614000-00615000 rw-p 00614000 00:00 0
00813000-00816000 rw-p 00013000 08:01 32823 /sbin/parted
010a9000-010eb000 rw-p 010a9000 00:00 0 [heap]
364fa00000-364fa03000 r-xp 00000000 08:01 851996 /lib64/libuuid.so.1.2
364fa03000-364fc03000 ---p 00003000 08:01 851996 /lib64/libuuid.so.1.2
364fc03000-364fc04000 rw-p 00003000 08:01 851996 /lib64/libuuid.so.1.2
3650a00000-3650a5b000 r-xp 00000000 08:01 852009 /lib64/libparted-1.8.so.8.0.0
3650a5b000-3650c5a000 ---p 0005b000 08:01 852009 /lib64/libparted-1.8.so.8.0.0
3650c5a000-3650c5e000 rw-p 0005a000 08:01 852009 /lib64/libparted-1.8.so.8.0.0
3650c5e000-3650c5f000 rw-p 3650c5e000 00:00 0
375e400000-375e437000 r-xp 00000000 08:01 122667 /lib64/libreadline.so.5.2
375e437000-375e637000 ---p 00037000 08:01 122667 /lib64/libreadline.so.5.2
375e637000-375e63f000 rw-p 00037000 08:01 122667 /lib64/libreadline.so.5.2
375e63f000-375e640000 rw-p 375e63f000 00:00 0
3c9d600000-3c9d620000 r-xp 00000000 08:01 852014 /lib64/ld-2.9.so
3c9d81f000-3c9d820000 r--p 0001f000 08:01 852014 /lib64/ld-2.9.so
3c9d820000-3c9d821000 rw-p 00020000 08:01 852014 /lib64/ld-2.9.so
3c9da00000-3c9db68000 r-xp 00000000 08:01 852015 /lib64/libc-2.9.so
3c9db68000-3c9dd68000 ---p 00168000 08:01 852015 /lib64/libc-2.9.so
3c9dd68000-3c9dd6c000 r--p 00168000 08:01 852015 /lib64/libc-2.9.so
3c9dd6c000-3c9dd6d000 rw-p 0016c000 08:01 852015 /lib64/libc-2.9.so
3c9dd6d000-3c9dd72000 rw-p 3c9dd6d000 00:00 0
3c9de00000-3c9de02000 r-xp 00000000 08:01 852016 /lib64/libdl-2.9.so
3c9de02000-3c9e002000 ---p 00002000 08:01 852016 /lib64/libdl-2.9.so
3c9e002000-3c9e003000 r--p 00002000 08:01 852016 /lib64/libdl-2.9.so
3c9e003000-3c9e004000 rw-p 00003000 08:01 852016 /lib64/libdl-2.9.so
3c9f600000-3c9f639000 r-xp 00000000 08:01 121997 /lib64/libsepol.so.1
3c9f639000-3c9f839000 ---p 00039000 08:01 121997 /lib64/libsepol.so.1
3c9f839000-3c9f83a000 rw-p 00039000 08:01 121997 /lib64/libsepol.so.1
3c9fa00000-3c9fa15000 r-xp 00000000 08:01 121998 /lib64/libdevmapper.so.1.02
3c9fa15000-3c9fc15000 ---p 00015000 08:01 121998 /lib64/libdevmapper.so.1.02
3c9fc15000-3c9fc17000 rw-p 00015000 08:01 121998 /lib64/libdevmapper.so.1.02
3ca4600000-3ca4616000 r-xp 00000000 08:01 121975 /lib64/libgcc_s-4.3.2-20081105.so.1
3ca4616000-3ca4816000 ---p 00016000 08:01 121975 /lib64/libgcc_s-4.3.2-20081105.so.1
3ca4816000-3ca4817000 rw-p 00016000 08:01 121975 /lib64/libgcc_s-4.3.2-20081105.so.1
3cafc00000-3cafc1d000 r-xp 00000000 08:01 120937 /lib64/libtinfo.so.5.6
3cafc1d000-3cafe1c000 ---p 0001d000 08:01 120937 /lib64/libtinfo.so.5.6
3cafe1c000-3cafe20000 rw-p 0001c000 08:01 120937 /lib64/libtinfo.so.5.6
3cafe20000-3cafe21000 rw-p 3cafe20000 00:00 0
7f375c000000-7f375c021000 rw-p 7f375c000000 00:00 0
7f375c021000-7f3760000000 ---p 7f375c021000 00:00 0
7f376047d000-7f3765162000 r--p 00000000 08:01 104535 /usr/lib/locale/locale-archive
7f3765162000-7f3765167000 rw-p 7f3765162000 00:00 0
7f376517b000-7f376517c000 rw-p 7f376517b000 00:00 0
7f376517c000-7f3765183000 r--s 00000000 08:01 123855 /usr/lib64/gconv/gconv-modules.cache
7f3765183000-7f3765185000 rw-p 7f3765183000 00:00 0
7fff6d170000-7fff6d185000 rw-p 7ffffffea000 00:00 0 [stack]
7fff6d1ff000-7fff6d200000 r-xp 7fff6d1ff000 00:00 0 [vdso]
ffffffffff600000-ffffffffff601000 r-xp 00000000 00:00 0 [vsyscall]
Aborted

So, the question how do i can remove this GPT partition table, seems it give alot of trouble, i just want to get normal partition table ?
Thanks

[daverj]

If you don't need anything on the drive maybe you can use dd to completely wipe it, then try partitioning it. As root:

dd if=/dev/zero of=/dev/sdb bs=1024

at 320G it will take a long while, but it might get you to what you need.

[sideways]

there is no point in completely wiping the disk, to simply reset it just overwrite the mbr

dd if=/dev/zero of=/dev/sdb bs=512 count=1

try running testdisk on the disk, it can often recover lost partitions. If that doesn't work recreate the entire partition with fdisk but do not recreate the filesystem and see if the files are still there.

[vaclinux]

Thanks man, I think i got it

[vaclinux]

I have tried to use this command

dd if=/dev/zero of=/dev/sdb bs=512 count=1

and then create a new partition used fdisk, but it still doesnt remove the gpt partition table,
I have as tried create recreate the filesytem use mkfs.vfat, but still it is not working to remove the gpt partition table

[sideways]

run

su -c 'parted /dev/sdb'

and type 'mktable'

[vaclinux]

Dude, it is just works,
now i can open it with gparted, after mktable.
So wat was the problem?
is it because i have corrupted partition table?

Btw, thanks for the reply

[sideways]

The partition table probably got corrupted.

parted is the recommended tool to use these days, fdisk is becoming deprecated.

'parted -l' is superior to 'fdisk -l' (run both as root)