Second disc has three cylinders less than the first - gmirror problem

V

vicf

I got 2 disks in this box and system says the second disk on sata1 port has 3 cylinders less than first disk on sata0 port, but the disks are the same model.

System is 8.1-RELEASE with GENERIC kernel
Motherboard INTEL D945GCL
Code: 
atapci0: Intel ICH7 UDMA100 controller
atapci1: Intel ICH7 SATA300 controller

Disks:
Code: 
ad4: 476940MB <WDC WD5000AAKS-00V1A0 05.01D05> at ata2-master UDMA100 SATA
ad6: 476938MB <WDC WD5000AAKS-00V1A0 05.01D05> at ata3-master UDMA100 SATA

In dmesg, I got this message after "GEOM_MIRROR: Device mirror/gm0 launched (1/1).":

Code: 
GEOM: mirror/gm0s1: geometry does not match label (16h,63s != 255h,63s).

fdisk /dev/ad4:

Code: 
parameters extracted from in-core disklabel are:
cylinders=969021 heads=16 sectors/track=63 (1008 blks/cyl)

The data for partition 1 is:
sysid 165 (0xa5),(FreeBSD/NetBSD/386BSD)
    start 63, size 976769073 (476938 Meg), flag 80 (active)
	beg: cyl 0/ head 1/ sector 1;
	end: cyl 1023/ head 15/ sector 63


fdisk /dev/ad6:

p
Code: 
arameters extracted from in-core disklabel are:
cylinders=969018 heads=16 sectors/track=63 (1008 blks/cyl)

The data for partition 1 is:
sysid 165 (0xa5),(FreeBSD/NetBSD/386BSD)
    start 63, size 976770081 (476938 Meg), flag 80 (active)
	beg: cyl 0/ head 1/ sector 1;
	end: cyl 313/ head 15/ sector 63

The problem is I'm trying to do gmirror the whole disk like handbook, but I got the "gmirror: Provider ad6 too small". I tried other 2 Samsumg disks (same model too) but FreeBSD got the second disk 3 cylinders less too.

I tried set geometry in fdisk, but no luck. It seems the fdisk can't save new geomatry value and show a "class not found" message. So I got 2 questions:

1. Any ideas why this happen and how to solve?

2. And there is some problem make a mirror in a partition (ad4s1) instead the whole disk (ad4)?
 
Create a single slice on each drive, make it the same size on each drive.

Then gmirror the slice, instead of the drives. Use ad4s1 and ad6s1 for the gmirror.
 
You could also build your gmirror with ad6 initially, then insert ad4 after. A slice is better IMHO, and it's what I do too.
 
I think I will do gmirror the slice. But the "always 3 cylinders less" is really annoying. Thanks for all the answers.
 
You must log in or register to reply here.
Back
Top