Changing Minor Numbers

To change the minor numbers so that they are the same on all systems, do the following:

1. On each system, identify the hardware path of the SCSI card to which the shared disk is attached. The hardware path for a SCSI device is in the format:
     <io-adapter>/<CARD-NUM>.<SCSI-ID>.<LUN-NUM>

   For example, if a SCSI disk (scsi 9, lun 0) is connected on IO Adapter 8, card#8, then the complete hardware path for the SCSI disk is: 8/8.9.0. The hardware path for the SCSI card (on which a disk of an array is connected) is: 8/8.

   You should be able to identify the shared disk device in the ioscan -fnC disk output based on how it is physically connected. For example, on System A:

   
     # ioscan -fnC disk
     Class I  H/W Path     Driver  S/W State   H/W Type  Description
     ===============================================================
     disk  0  8/8.9.0      sdisk   CLAIMED     DEVICE    SEAGATE 
      ST34563WC
                  /dev/dsk/c0t6d0  /dev/rdsk/c0t6d0
     disk  1  10/12/5.2.0  sdisk   CLAIMED     DEVICE    TOSHIBA
     XM-5701TA
                  /dev/dsk/c1t2d0  /dev/rdsk/c1t2d0
2. Identify the largest ICIN in use among all devices on each system by running the command ioscan -fnC ext_bus. For example, on System A, the largest ICIN number listed under the heading "I" is 3:
     # ioscan -fnC ext_bus
     Class     I  H/W Path  Driver      S/W State H/W Type  Description 
     ===================================================================
     ext_bus   0  8/4       c720        CLAIMED   INTERFACE GSC add-on 
     Fast/Wide SCSI Interface
     ext_bus   1  8/8       c720        CLAIMED   INTERFACE GSC add-on
     Fast/Wide SCSI Interface
     ext_bus   3  8/16/0    CentIf      CLAIMED   INTERFACE Built-in  
     Parallel Interface
                         /dev/c3t0d0_lp
     ext_bus   2  8/16/5    c720        CLAIMED   INTERFACE Built-in SCSI

   On System B, the largest ICIN number is 4:

   
     # ioscan -fnC ext_bus
     Class     I  H/W Path  Driver      S/W State H/W Type  Description
     ===================================================================
     ext_bus   0  8/4       c720        CLAIMED   INTERFACE GSC add-on
     Fast/Wide SCSI Interface
     ext_bus   1  8/6       c720        CLAIMED   INTERFACE GSC add-on
     Fast/Wide SCSI Interface
     ext_bus   2  8/8       c720        CLAIMED   INTERFACE GSC add-on
     Fast/Wide SCSI Interface
     ext_bus   4  8/16/0    CentIf      CLAIMED   INTERFACE Built-in
     Parallel Interface
                         /dev/c3t0d0_lp
     ext_bus   3  8/16/5    c720        CLAIMED   INTERFACE Built-in SCSI
3. Choose a unique ICIN number. Since the highest ICIN assigned on System A is 3, and the highest assigned ICIN on System B is 4, an acceptable unique ICIN is 5, one greater than 4, the current maximum.
4. On each system, create an ASCII "mapfile" with the following format:
     h/w path                class-of-device                 new ICIN

   Continuing the example above, the mapfile on System A should resemble:

   
     8/8                     ext_bus                         5

   And on System B, the file should resemble:

   
     8/8                     ext_bus                         5

   The class-of-device and new ICIN should be same for all systems as required for NFS failover to work correctly. However, since hardware path is system-specific, it may vary for each system.

5. On each system, run the command:
     # ioinit -f mapfile -r
6. Reboot the systems.
7. When the systems come up, run the command:
     # insf -e
8. Now the minor number for the shared device is the same on all systems and NFS failover is allowed.