kern/159091: GEOM fails to scan nested partitions to create subdevices

[Michael Wayne]

>Number:         159091
>Category:       kern
>Synopsis:       GEOM fails to scan nested partitions to create subdevices
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Thu Jul 21 16:50:12 UTC 2011
>Closed-Date:
>Last-Modified:
>Originator:     Michael Wayne
>Release:        6.3 / 8.2
>Organization:
Msen, Inc.
>Environment:
8.2-RELEASE FreeBSD 8.2-RELEASE #0
>Description:
Since at least 2006, we have used bsdlabel on slices to make "nested" slices. An example would be:
`bsdlabel -w /dev/ad0s1e` - creating /dev/ad0s1ea

In trying to set up a new server, I did this in the expected way. bsdlabel works correctly on 8.2, creating the nested slices. However, GEOM fails to create the appropriate /dev entry on 8.2 (works correctly on 6.X, have not tried on 7.X).

I brought this up on #freebsd, the suggestion was to use ZFS. But, this means that it is not possible to upgrade existing 6.X servers that use this feature to a recent FreeBSD. I am presuming that this is just an oversight.

Here is a thread from 2006 mentioning this feature:
http://freebsd.1045724.n5.nabble.com/disklabel-differences-FreeBSD-DragonFly-td4038161i20.html

>How-To-Repeat:
bsdlabel -w <slice>
bsdlabel -e <slice>
Create several nested slices. GEOM will not create the appropriate /dev subdevices
>Fix:


>Release-Note:
>Audit-Trail:
>Unformatted: