Solaris: Workaround for incorrect LUN size issue ~ Creation Zone

Scenario:
You created a logical drive of capacity x GB, and mapped it so there is a LUN (Logical Unit Number) with size x GB. When you run format command, Solaris shows incorrect size for the logical drive.

eg.,
Partition table showing only 409 GB, where it is supposed to show 816 GB.

partition> p
Current partition table (original):
Total disk cylinders available: 53233 + 2 (reserved cylinders)

Part      Tag    Flag     Cylinders         Size            Blocks
  0       root    wm       0 -    16      133.88MB    (17/0/0)       274193
  1       swap    wu      17 -    33      133.88MB    (17/0/0)       274193
  2     backup    wu       0 - 53232      409.41GB    (53233/0/0) 858595057
  3 unassigned    wm       0                0         (0/0/0)             0
  4 unassigned    wm       0                0         (0/0/0)             0
  5 unassigned    wm       0                0         (0/0/0)             0
  6        usr    wm      34 - 53232      409.15GB    (53199/0/0) 858046671
  7 unassigned    wm       0                0         (0/0/0)             0

It could be a Solaris bug. However the following steps may fix the issue and show the real size of the LUN.

Note:
I'm no storage expert - just outlining the steps that helped me resolving the issue. May be there are better/simpler ways to resolve this issue which I do not know yet.

Steps:

Run the following commands as root user:

# touch /reconfigure
# reboot

# format

Select the disk and check the partition table. Do you see the configured size? If yes, you are done - stop here. If not, go to the next step.

eg., continued ..

# format
Searching for disks...done


AVAILABLE DISK SELECTIONS:
       0. c1t0d0 
          /pci@7c0/pci@0/pci@1/pci@0,2/LSILogic,sas@2/sd@0,0
       1. c1t1d0 
          /pci@7c0/pci@0/pci@1/pci@0,2/LSILogic,sas@2/sd@1,0
       2. c2t216000C0FFD7E5FBd0 <SUN-StorEdge3510-411I cyl 65533 alt 2 hd 64 sec 408>
          /pci@7c0/pci@0/pci@1/pci@0,2/SUNW,qlc@1/fp@0,0/ssd@w216000c0ffd7e5fb,0
       3. c2t216000C0FFD7E5FBd1 <SUN-StorEdge3510-411I cyl 47588 alt 2 hd 64 sec 255>
          /pci@7c0/pci@0/pci@1/pci@0,2/SUNW,qlc@1/fp@0,0/ssd@w216000c0ffd7e5fb,1

Specify disk (enter its number): 2
selecting c2t216000C0FFD7E5FBd0
[disk formatted]
Warning: Current Disk has mounted partitions.


FORMAT MENU:
        disk       - select a disk
        type       - select (define) a disk type
        partition  - select (define) a partition table
        current    - describe the current disk
        format     - format and analyze the disk
        repair     - repair a defective sector
        label      - write label to the disk
        analyze    - surface analysis
        defect     - defect list management
        backup     - search for backup labels
        verify     - read and display labels
        save       - save new disk/partition definitions
        inquiry    - show vendor, product and revision
        volname    - set 8-character volume name
        !     - execute , then return
        quit

format> p

PARTITION MENU:
        0      - change `0' partition
        1      - change `1' partition
        2      - change `2' partition
        3      - change `3' partition
        4      - change `4' partition
        5      - change `5' partition
        6      - change `6' partition
        7      - change `7' partition
        select - select a predefined table
        modify - modify a predefined partition table
        name   - name the current table
        print  - display the current table
        label  - write partition map and label to the disk
        ! - execute , then return
        quit

partition> p
Current partition table (original):
Total disk cylinders available: 53233 + 2 (reserved cylinders)

Part      Tag    Flag     Cylinders         Size            Blocks
  0       root    wm       0 -    16      133.88MB    (17/0/0)       274193
  1       swap    wu      17 -    33      133.88MB    (17/0/0)       274193
  2     backup    wu       0 - 53232      409.41GB    (53233/0/0) 858595057
  3 unassigned    wm       0                0         (0/0/0)             0
  4 unassigned    wm       0                0         (0/0/0)             0
  5 unassigned    wm       0                0         (0/0/0)             0
  6        usr    wm      34 - 53232      409.15GB    (53199/0/0) 858046671
  7 unassigned    wm       0                0         (0/0/0)             0

In this example the issue wasn't resolved just by rebooting the server with /reconfigure file in root file system.

Now go back one level by quitting the partition table screen; and then type in the word 'type'. When you are shown the available drive types, select '0. Auto configure' option by typing 0. Usually this step would fix the issue and show the right LUN size. Just label the disk by selecting 'label' option and verify the partition table one more time to see if it is showing the right size.

eg., continued ..

partition> q

format> type

AVAILABLE DRIVE TYPES:
        0. Auto configure
        1. Quantum ProDrive 80S
        2. Quantum ProDrive 105S
        3. CDC Wren IV 94171-344
        4. SUN0104
        5. SUN0207
        6. SUN0327
        7. SUN0340
        8. SUN0424
        9. SUN0535
        10. SUN0669
        11. SUN1.0G
        12. SUN1.05
        13. SUN1.3G
        14. SUN2.1G
        15. SUN2.9G
        16. Zip 100
        17. Zip 250
        18. Peerless 10GB
        19. SUN72G
        20. SUN-StorEdge3510-411I
        21. SUN-StorEdge3510-411I
        22. SUN-StorEdge3510-411I
        23. other

Specify disk type (enter its number)[21]: 0
c2t216000C0FFD7E5FBd0: configured with capacity of 815.96GB
<SUN-StorEdge3510-411I cyl 65533 alt 2 hd 64 sec 408>
selecting c2t216000C0FFD7E5FBd0
[disk formatted]

format> current
Current Disk = c2t216000C0FFD7E5FBd0
<SUN-StorEdge3510-411I cyl 65533 alt 2 hd 64 sec 408>
/pci@7c0/pci@0/pci@1/pci@0,2/SUNW,qlc@1/fp@0,0/ssd@w216000c0ffd7e5fb,0

format> label
Ready to label disk, continue? y

format> p

PARTITION MENU:
        0      - change `0' partition
        1      - change `1' partition
        2      - change `2' partition
        3      - change `3' partition
        4      - change `4' partition
        5      - change `5' partition
        6      - change `6' partition
        7      - change `7' partition
        select - select a predefined table
        modify - modify a predefined partition table
        name   - name the current table
        print  - display the current table
        label  - write partition map and label to the disk
        ! - execute , then return
        quit

partition> p
Current partition table (default):
Total disk cylinders available: 65533 + 2 (reserved cylinders)

Part      Tag    Flag     Cylinders         Size            Blocks
  0       root    wm       0 -    10      140.25MB    (11/0/0)        287232
  1       swap    wu      11 -    21      140.25MB    (11/0/0)        287232
  2     backup    wu       0 - 65532      815.96GB    (65533/0/0) 1711197696
  3 unassigned    wm       0                0         (0/0/0)              0
  4 unassigned    wm       0                0         (0/0/0)              0
  5 unassigned    wm       0                0         (0/0/0)              0
  6        usr    wm      22 - 65532      815.69GB    (65511/0/0) 1710623232
  7 unassigned    wm       0                0         (0/0/0)              0

partition> q

In this particular example, we can see that the issue is resolved. But in some other cases it may not fix the real issue. In such scenarios go ahead and file a bug against Solaris storage management at bugs.opensolaris.org.

Acknowledgements:
Thanks to Robert Cohen for the tip in thread: Solaris 'format' not seeing new size of LUN after expansion on SAN.
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Creation Zone

Sunday, 19 November 2006

Solaris: Workaround for incorrect LUN size issue

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