gmirror refused to connect second disk after a reboot

[Edwin Groothuis]

For two years I've had a happy gmirror RAID1 system. And a week or
three ago I was found a degraded system due to a broken disk.

I tried to replace the disk, first with one three sectors too small
which didn't want to be entered in the array (as excepted), then
with a same brand/type one which I added without a problem. Rebuilding,
everything okay.

    [~] edwin at k7>sudo fdisk -s /dev/ad1
    /dev/ad1: 1938021 cyl 16 hd 63 sec
    Part        Start        Size Type Flags
       1:          63  1953520002 0xa5 0x00
    [~] edwin at k7>sudo fdisk -s /dev/ad3
    /dev/ad3: 1938021 cyl 16 hd 63 sec
    Part        Start        Size Type Flags
       1:          63  1953520002 0xa5 0x80

    [~] edwin at k7>gmirror status
          Name    Status  Components
    mirror/gm0  COMPLETE  ad1
			  ad3


Until after a reboot, then GEOM complains about:

    GEOM: ad3s1: geometry does not match label (255h,63s != 16h,63s).
    GEOM_MIRROR: Force device gm0 start due to timeout.
    GEOM_MIRROR: Device mirror/gm0 launched (1/2).

    [~] edwin at k7>gmirror status
	  Name    Status  Components
	  mirror/gm0  DEGRADED  ad1

Forgetting and re-inserting the ad3 does attach it again and rebuild
everything, until the next reboot.

Booting from ad3 instead of from ad1 results in the same result.
This device is running 8.0-STABLE r204385.


Who has any idea what is going wrong here and which smart commands
I can to overcome this silly issues or are any clues which commands
I should run next to get more information?

Thanks heaps,
Edwin

-- 
Edwin Groothuis		Website: http://www.mavetju.org/
edwin at mavetju.org	Weblog:  http://www.mavetju.org/weblog/