The release of microcode 01-15-39-00/05 included new support
 for Sun Cluster 3.0. This new functionality requires the user 
 to set system option 185 to "on" for the 99x0 Subsystem. This
 setting creates a unique DID (Disk ID) for all luns on the
 array. This infodoc details the procedure to set this option. 

 Note: This option does NOT have to be set for Sun Cluster 2.2


  1. From the SVP enter a <CTRL><SHIFT>M
  2. You will get a password box. The password is mode
  3. The SVP will go from "View Mode" to "Mode Mode"
     (that's right, "mode mode")
  4. Select the Install button.
  5. Select the Change Configuration button.
  6. Select the System Option button.
  7. Within System Option, there will now appear a "mode"
     button. select that, and you will get a screen with available
     bits to set for system options 0-255. Move up to 185, set
     the bit and hit OK.
  8. Confirm saved changes.
            

Reference internal Hitachi doc ECN-M033 for Ucode 01-15-39-00/05.