amd64/156106: boot0 fails to start

[Alexander Pyhalov]

>Number:         156106
>Category:       amd64
>Synopsis:       boot0 fails to start
>Confidential:   no
>Severity:       serious
>Priority:       low
>Responsible:    freebsd-amd64
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Fri Apr 01 10:50:08 UTC 2011
>Closed-Date:
>Last-Modified:
>Originator:     Alexander Pyhalov
>Release:        8.2
>Organization:
SFEDU
>Environment:
uname -a 
FreeBSD fbsdhost5.xx 8.2-RELEASE FreeBSD 8.2-RELEASE #0 r219027M: Wed Mar  9 15:12:21 MSK 2011     alp at yy:/usr/obj/usr/src-releng-8.2/sys/ibm-hs-21xm-vnet-amd64.releng-8.2  amd64
>Description:
We have IBM amd64 blade, which is connected to EMC storage with 4 paths (2 paths per FC card). One lun is provided to host. Initially we had the following bsdlabel:
#        size   offset    fstype   [fsize bsize bps/cpg]
  a: 18863577       16    4.2BSD        0     0     0 # /
  b:  4194304 18863593      swap                     
  c: 33543657        0    unused        0     0         # "raw" part, don't edit
  d:  2097152 23057897    4.2BSD        0     0     0 # /tmp
  e:  8388608 25155049    4.2BSD        0     0     0 # /var

With such bsdlabel boot0 randomly doesn't show prompt (F1: Disk1, etc...) and system boot stalls. At least it happenes once in 6-7 boots (usually faster).

After resetting bsdlabel to (changing partition types to unused):
#        size   offset    fstype   [fsize bsize bps/cpg]
  a: 18863577       16    unused        0     0       
  b:  4194304 18863593      swap                    
  c: 33543657        0    unused        0     0         # "raw" part, don't edit
  d:  2097152 23057897    unused        0     0       
  e:  8388608 25155049    unused        0     0       
the system boots perfectly (I've booted 11 times in a row without issues).

The problem is that on 2 other blades we had the similar situation, but somehow with bios settings we managed to make that systems boot every time. This time we copied bios settings from successful installation - this didn't help. Other OSes (Ununtu Linux 10.10,OpenIndiana b148) boots successfully without any tweaking on all blades. FreeBSD boots only whith fs labels changed to "unused".

>How-To-Repeat:

>Fix:
Change FS labels to "unknown"

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