HOWTO Mirror HPUX Root Disk

Step 1: Make ensure you have the right disk 
# ioscan –fnC disk
# diskinfo /dev/rdsk/c0t4d0

The command below should fail if the disk is completely empty
confirming its the right disk to use as a mirror!
# pvdisplay –v /dev/dsk/c0t4d0  

Step 2: Create bootable physical volume
# pvcreate –B /dev/rdsk/c0t4d0

Step 3: Add disk to existing volume group i.e  vg03
# vgextend  /dev/vg03  /dev/dsk/c0t4d0

NOTE: Perform Steps 4 and 5 if it’s a boot disk 
      and not just a data disk.

Step 4: Place boot utilities in boot area of the disk
# mkboot  /dev/rdsk/c0t4d0

Step 5: Point disk to /stand dir
# mkboot  -a  “hpux –lq (;0)/stand/vmunix” /dev/rdsk/c0t4d0

NOTE: Switch "-lq" is needed only if 2 disks exist in the mirror.
Otherwise, when booting it will not boot if one of the disks is bad.
Perform: ISL >  hpux -lq

Confirm disk is part of volume group:
# vgdisplay –v   /dev/vg03
# pvdisplay –v /dev/dsk/c0t4d0  


Stp 6: CREATE the logical volume that exist in the current disk
       On the new disk in the SAME SEQUENCE – as they appear in the
       pvdisplay –v /dev/dsk/c0t6d0

 lvextend   -m  1  /dev/vg03/lvol1  /dev/dsk/c0t4d0
 lvextend   -m  1  /dev/vg03/lvol2  /dev/dsk/c0t4d0
 lvextend   -m  1  /dev/vg03/lvol4  /dev/dsk/c0t4d0
 lvextend   -m  1  /dev/vg03/lvol5  /dev/dsk/c0t4d0     ----      etc….

Step 7: Check with "lvlnboot  -v"  to see both disks
# lvlnboot -v /dev/vg03

Boot Definitions for Volume Group /dev/vg03:
Physical Volumes belonging in Root Volume Group:
        /dev/dsk/c0t6d0 (10/0.6.0) -- Boot Disk
        /dev/dsk/c0t4d0 (10/0.4.0) -- Boot Disk
Boot: lvol1     on:     /dev/dsk/c0t6d0
                        /dev/dsk/c0t4d0
Root: lvol3     on:     /dev/dsk/c0t6d0
                        /dev/dsk/c0t4d0
Swap: lvol2     on:     /dev/dsk/c0t6d0
                        /dev/dsk/c0t4d0
Dump: lvol2     on:     /dev/dsk/c0t6d0, 0


Step 8: Check with lvdisplay  -v  /dev/vg03/lvol[ 1 ]
        which should show both disks available and should
        both be  ‘current’  and NOT  ‘stale’.

# lvdisplay -v /dev/vg03/lvol1 | pg
--- Logical volumes ---
LV Name                     /dev/vg03/lvol1
VG Name                     /dev/vg03
LV Permission               read/write
LV Status                   available/syncd
Mirror copies               1
Consistency Recovery        MWC
Schedule                    parallel
LV Size (Mbytes)            100
Current LE                  25
Allocated PE                50
Stripes                     0
Stripe Size (Kbytes)        0
Bad block                   off
Allocation                  strict/contiguous
IO Timeout (Seconds)        default

   --- Distribution of logical volume ---
   PV Name            LE on PV  PE on PV
   /dev/dsk/c0t6d0    25        25
   /dev/dsk/c0t4d0    25        25

   --- Logical extents ---
   LE    PV1                PE1   Status 1 PV2                PE2   Status 2
   00000 /dev/dsk/c0t6d0    00000 current  /dev/dsk/c0t4d0    00000 current
   00001 /dev/dsk/c0t6d0    00001 current  /dev/dsk/c0t4d0    00001 current
   00002 /dev/dsk/c0t6d0    00002 current  /dev/dsk/c0t4d0    00002 current
   00003 /dev/dsk/c0t6d0    00003 current  /dev/dsk/c0t4d0    00003 current
   00004 /dev/dsk/c0t6d0    00004 current  /dev/dsk/c0t4d0    00004 current
   00005 /dev/dsk/c0t6d0    00005 current  /dev/dsk/c0t4d0    00005 current
   00006 /dev/dsk/c0t6d0    00006 current  /dev/dsk/c0t4d0    00006 current
   00007 /dev/dsk/c0t6d0    00007 current  /dev/dsk/c0t4d0    00007 current
   00008 /dev/dsk/c0t6d0    00008 current  /dev/dsk/c0t4d0    00008 current

Step 9: Set the new disk to be secondary boot device 
        either in IPL  or at command level :

 setboot   = displays

# setboot
Primary bootpath : 10/0.6.0
Alternate bootpath : 10/0.4.0

Autoboot is ON (enabled)
Autosearch is OFF (disabled)
 
# setboot   -a  10/0.4.0      [  before this was the tape drive   10/12/5.0.0  ]


Step 10:
# Shutdown –r –y 0

Interact with ISL
BO ALT