Note A replacement disk should have the same disk geometry as the disk that failed. That is, the replacement disk should have the same bytes per sector, sectors per track, tracks per cylinder and sectors per cylinder, same number of cylinders, and the same number of accessible cylinders.

Use the prtvtoc command to obtain disk information.

1. If the replacement disk is the same size as the disk that failed, confirm that the geometry of the replacement disk is the same, using the prtvtoc command.

Example:

 

In below example c15t0d22s2 is the replacement disk and c15t0d23s2 is a disk of the same disk group and volume.


***********************

Geometry of c15t0d22s2:
***********************
# prtvtoc /dev/rdsk/c15t0d22s2
*/dev/rdsk/c15t0d22s2 partition map
*
* Dimensions:
*     512 bytes/sector
*     254 sectors/track
*      20tracks/cylinder
*    5080sectors/cylinder
*   13995cylinders
*   13993accessible cylinders
*Flags:
*   1:unmountable
*  10:read-only
*
*Unallocated space:
*      First    Sector    Last
*      Sector    Count    Sector
*        5080      5080    10159
*
*                                  First       Sector          Last
*Partition  Tag  Flags    Sector    Count           Sector        Mount Directory
     2         5    01          0          71084440      71084439
     3        15    01          0            5080            5079
      4        14    01      10160      71074280      71084439

 

Geometry of c15t0d23s2:
***********************
# prtvtoc /dev/rdsk/c15t0d23s2
*/dev/rdsk/c15t0d23s2 partition map
*
* Dimensions:
*     512 bytes/sector
*     254 sectors/track
*      20tracks/cylinder
*    5080sectors/cylinder
*   13998cylinders
*   13996accessiblecylinders
*
*Flags:
*   1:unmountable
*  10:read-only
*
*                                    First        Sector        Last
*Partition  Tag     Flags    Sector    Count          Sector              Mount Directory
     2        5        01          0          71099680    71099679
     3        15      01          0              5080          5079
     4        14       01      5080         71094600    71099679

Although both devices are 33Gs in size, the total number of sectors for c15t0d22s2 calculates is slightly smaller than the total number of sectors for c15t0d23s2.

 

Since the public region consists of the entire size of the disk (minus the size of the private region),  Volume Manager reports the 'Disk public region is too small' error.

There are two ways to correct this issue:

 

a) Replace the failed disk with a larger disk.

 

OR

 

b) Replace the failed disk with a disk consisting of the same geometry.