Verify Disk is Present When Booting From Alternate Media

Asset ID:	1-71-1005531.1
Update Date:	2017-03-29
Keywords:

Solution Type Technical Instruction Sure

Solution 1005531.1 : Verify Disk is Present When Booting From Alternate Media

Applies to:

Sun Netra 1290 Server - Version All Versions and later
Sun Fire V210 Server - Version All Versions and later
Sun Fire V245 Server - Version All Versions and later
Sun Fire V250 Server - Version All Versions and later
Sun Fire V440 Server - Version All Versions and later
All Platforms

Goal

This document will help determine that status of a suspect disk, and verify Good OS Disk(s) are available for boot.

The disk might be suspected to be defective, in need of file system check (fsck), and the system may be unable to boot if the disk involved is the boot device. Utilize this method to validate the disk's status when you are able to boot off an alternate device.

Solution

To determine if a disk can be seen, the system must be booted by a known good operating environment.
A known good environment would be achieved by being booted off either cdrom (DVD) or off a jumpstart image.

To do this, perform the following:

ok> setenv auto-boot? false

The above step will prevent automatic booting after the next step is performed: set this back to true once the boot issue is fixed.

ok> reset-all

The above step will give us a clean environment for the next step

ok> probe-scsi-all

The above step will help us determine if the internal Disks are visible: also note the Controller Number and the number of disks displayed under each one.

Once the disks are visible in probe-scsi-all

ok> boot -s cdrom
or
ok> boot -s net

Note that, the cdrom path and net path needs to be verified using devalias/show-disks/watch-net-all

The system will boot to single user mode. At this point format will show all the drive the system can see.

# format
Searching for disks...done
AVAILABLE DISK SELECTIONS:
       0. c1t1d0
          /pci@8,600000/SUNW,qlc@4/fp@0,0/ssd@w21000004cf8ebc46,0
       1. c1t2d0
          /pci@8,600000/SUNW,qlc@4/fp@0,0/ssd@w210000186277b043,0
Specify disk (enter its number): 0
selecting c1t1d0
[disk formatted]

Select the drive that is suspected of having a problem. In this case, c1t1d0 or 0.

Then check the partition table of the drive to find the root slice.

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> partition

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> print
Current partition table (original):
Total disk cylinders available: 14087 + 2 (reserved cylinders)
Part      Tag    Flag     Cylinders         Size            Blocks
0       root    wm       0 - 13673       66.35GB    (13674/0/0) 139146624
1       swap    wu   13674 - 14086        2.00GB    (413/0/0)     4202688
2     backup    wm       0 - 14086       68.35GB    (14087/0/0) 143349312
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 unassigned    wm       0                0         (0/0/0)             0
7 unassigned    wm       0                0         (0/0/0)             0

partition> quit

Here we see the root slice is partition 0.

At this point the drive can be checked and mounted - if there is a non-RAID filesystem on the drive.

Start with checking the file system.

# fsck /dev/rdsk/c1t1d0s0 (this is the drive info we just got from format)

Fix any errors that are reported. Run fsck till it runs with no errors. Then it is time to mount the drive.

To mount the drive:

# mount /dev/dsk/c1t0d0s0 /a

Change directory onto the drive see if there is a file system there.

# cd /a

At this point the drive should be available for use.

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