Remove file system from Solaris disk

UNIX Solaris
1

hi,
i have created a file system using newfs command in solaris 10, later i got error messages from the database which i am using. May be database using the disk also.
My question is how to remove file system from the disk.

Thanks

2

There's many ways to "remove file system from the disk", but why would you want to do so? If errors occur, what be the error msgs?

3

What database?
What error messages?

4

Thanks for your reply,

Actually i am using oracle 11g database and i have perform newfs command on the disk which was added to oracle (ASM) database.
And the error which i am receiving is oracle data block corruption (ORA-01110,ORA-01578)when i access the data.

is there any way to undo newfs command which i have performed.
Thanks

5

You have overwritten the ASM data by creating a file system on a device already used by the database. This quite a destructive action as there is no "undo-newfs" command.

I'm no ASM expert but I guess the proper way to recover the system would be to rebuild the ASM storage and restore from backup.

6

Thanks for your reply, one thing which i want to discuss is that while creating a disk partition for database, in partition table we select part 6 tag usr and starting cylinder 1 to create a slice .
While we run newfs command on part 2 tag backup and starting cylinder 0 .

So in my opinion newfs command run on different slice , so it does not format the whole disk , disk is still available on ASM storage only it changes the header information or file system information.
My question will be is there any way to revert the disk header information so that the data in our database can be corrected.

7

Slice 2 is a whole disk
Below is output from format

Total disk cylinders available: 65533 + 2 (reserved cylinders)

Part      Tag    Flag     Cylinders         Size            Blocks
  0       root    wm       0 - 26214        8.00GB    (26215/0/0) 16777600
  1       swap    wu   26215 - 32768        2.00GB    (6554/0/0)   4194560
  2     backup    wm       0 - 65532       20.00GB    (65533/0/0) 41941120
  3 unassigned    wm   32769 - 65532       10.00GB    (32764/0/0) 20968960
  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

In first line you can see that total disk cylinders is 65533.
Slice number 2 starts at cylinder 0 and ends at 65532. So the total number of used cylinders is 65533, what means that slice numer 2 uses whole disk. It is a special type of slice which overwrite other slices.
About Disk Slices (System Administration Guide: Devices and File Systems)

8

Indeed, using slice 2 was even more a destructive and un-restorable action.

You have also destroyed (by randomly overwriting some areas) other slices that might have been used on that disk.