When replacing a failed disk under Veritas control in the 
A5000 (Photon), one cannot simply pull out the disk and replace it
with a new one as with other type of drive.  Because of the
fact that each disk has a unique world-wide number (WWN), the following
procedure must be followed to correctly remove and replace any disk in
an A5000 (Sun Enterprise Network Array (SENA)).

If the correct procedure is not followed, Volume Manager may display the 
message:

	device cxtxxdxsx online failed : device path not valid

when attempting to get the new disk online.



SOLUTION SUMMARY:

The following procedure illustrates the correct sequence of commands needed to
replace a disk in an A5000 array if Volume Manager is being used.

1) Inform Volume Manager you wish to remove the disk:

       # vxdiskadm option 4 (Remove a disk for replacement)

2) Offline the device:

       # vxdiskadm option 11 (Disable (offline) a disk device)
          (use the c#t#d# name)
           or
       GUI Advanced-Ops->Disk->Offline
          (use the Disks window; highight c#t#d#s#)

3) Remove the device and device nodes:

     # luxadm remove_device enclosurename,[f|r]slot#

          where: enclosure name is the name of A5000 as 
                 reported by luxadm probe
                 
                 f- front panel
                 r- rear panel
                 
         example:  front panel slot 3 with box name = saturn
        
      # luxadm remove_device saturn,f3
       


 Notes:
 
 A.   If removal says  "device busy" and does not continue the 
        removal, do either:
 
     1. On the front panel display,  manually select the
        disk to be replaced and stop it

                      or

     2.  force the disk removal with:
    
         # luxadm -F remove_device enclosurename,[f|r]slot#


 B.   If this is a multi-initiated array (i.e., if there are more than one
      systems connected to this disk drive), you must perform the previous
      command on every system connected to the array.
 

4) Run the following command and then when prompted physically replace
   the disk

      # luxadm insert_device enclosurename,[f|r]slot#

   to create the new device and device nodes.  Again, on a multi-initiated
   array, this command must be performed on all systems connected to the
   array.

5) Inform Volume Manager of the configuration changes with the command

      # vxdctl enable

6) Bring the disk back online in Volume Manager:

      # vxdiskadm option 5 (Replace a failed or removed disk)