Date: Wed, 17 Feb 2010 12:58:46 -0600 From: Bob Willcox <bob@immure.com> To: questions list <freebsd-questions@freebsd.org> Subject: fdisk fails with "Class not found" Message-ID: <20100217185846.GA85769@rancor.immure.com>
next in thread | raw e-mail | index | archive | help
I am trying to change the sysid of a slice (partition) on my disk from 5 to
165. When it gets to the point of writing sector 0 it always fails with:
fdisk: Class not found
fdisk: Failed to write sector zero
Can someone please tell me what this means, and how do I fix it?
I have included the output from an fdisk attempt below.
Thanks,
Bob
root@tavion:10 /usr/home/bob> fdisk -uv
******* Working on device /dev/ad4 *******
parameters extracted from in-core disklabel are:
cylinders=969021 heads=16 sectors/track=63 (1008 blks/cyl)
Figures below won't work with BIOS for partitions not in cyl 1
parameters to be used for BIOS calculations are:
cylinders=969021 heads=16 sectors/track=63 (1008 blks/cyl)
Do you want to change our idea of what BIOS thinks ? [n]
Media sector size is 512
Warning: BIOS sector numbering starts with sector 1
Information from DOS bootblock is:
The data for partition 1 is:
sysid 165 (0xa5),(FreeBSD/NetBSD/386BSD)
start 63, size 524286945 (255999 Meg), flag 80 (active)
beg: cyl 0/ head 1/ sector 1;
end: cyl 1023/ head 15/ sector 63
Do you want to change it? [n]
The data for partition 2 is:
sysid 5 (0x05),(Extended DOS)
start 524297340, size 452470725 (220932 Meg), flag 0
beg: cyl 1023/ head 255/ sector 63;
end: cyl 1023/ head 14/ sector 63
Do you want to change it? [n] y
Supply a decimal value for "sysid (165=FreeBSD)" [5] 165
Supply a decimal value for "start" [524297340]
Supply a decimal value for "size" [452470725]
Explicitly specify beg/end address ? [n]
sysid 165 (0xa5),(FreeBSD/NetBSD/386BSD)
start 524297340, size 452470725 (220932 Meg), flag 0
beg: cyl 968/ head 4/ sector 1;
end: cyl 311/ head 14/ sector 63
Are we happy with this entry? [n] y
The data for partition 3 is:
<UNUSED>
Do you want to change it? [n]
The data for partition 4 is:
<UNUSED>
Do you want to change it? [n]
Partition 1 is marked active
Do you want to change the active partition? [n]
We haven't changed the partition table yet. This is your last chance.
parameters extracted from in-core disklabel are:
cylinders=969021 heads=16 sectors/track=63 (1008 blks/cyl)
Figures below won't work with BIOS for partitions not in cyl 1
parameters to be used for BIOS calculations are:
cylinders=969021 heads=16 sectors/track=63 (1008 blks/cyl)
Information from DOS bootblock is:
1: sysid 165 (0xa5),(FreeBSD/NetBSD/386BSD)
start 63, size 524286945 (255999 Meg), flag 80 (active)
beg: cyl 0/ head 1/ sector 1;
end: cyl 1023/ head 15/ sector 63
2: sysid 165 (0xa5),(FreeBSD/NetBSD/386BSD)
start 524297340, size 452470725 (220932 Meg), flag 0
beg: cyl 968/ head 4/ sector 1;
end: cyl 311/ head 14/ sector 63
3: <UNUSED>
4: <UNUSED>
Should we write new partition table? [n] y
fdisk: Class not found
fdisk: Failed to write sector zero
--
Bob Willcox Stock's Observation:
bob@immure.com You no sooner get your head above water
Austin, TX but what someone pulls your flippers off.
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20100217185846.GA85769>