Conference aosg::lsm

764.0. "Steps to restore an LSM encapsulated ADVFS root?" by CSC32::COLTER () Sat Mar 08 1997 06:17

Please look at this note and fix it if you find errors.
    
    
PROBLEM:

  The customer wiped out both mirrors on his LSM encapsulated ADVFS root
  disk set, on both systems on his ASE cluster. 

Steps to restore an LSM encapsulated ADVFS root.
===============================================

1.  zero out all the old lsm meta data  (on both mirror disks)
        disklabel -z rzb18
	dd if=/vmunix of=/dev/rrz0c  (wipes out first 16 blocks of the
				      disk which contains metadata)

2.  disklabel -wr   /dev/rrz0c rz28

3.  disklabel -e    /dev/rz0a Edits an existing label 
		    (to restore the partition, you need to know ed).

4.  restore the ADVFS fileset according to an article, [ADVFS-OSF] How To 
    Recover Your System Disk When They Are AdvFS Filesystems. Always do
    root first and then boot from the disk that you have created.  "mkfdmn 
    -o" is a useful switch, remember it.  Do not try to restore /usr or
    any other fileset from the CDROM  system, as there will not be enough
    memory.  In general, you will need enough memory to contain your file
    system as well as the vrestore.  

5.  AOSG::LSM note 639.1 begins right here, we need to encapsulate the advfs
    fileset into an LSM volume.  To do that we must be able to run 
    "/sbin/lsmbstartup -n".  Before we can run this program, we need to
    be able to boot an ADVFS file system.  To do this we must first remove 
    all the references to lsm included in files like fstab, swapdefault, 
    sysconfigtab, inittab etc... (each time you'll forgot one and you'll 
    have to reboot again and modify/move the offending file).

6.  After you have sucessfully booted the advfs file set then you encapsulate
    the root by executing /usr/sbin/voladvdomencap domain ( see the parachute
    guide or LSM manual)

7.  mkfdmn -o is a useful switch.