recover a droppped diskgroup

[satish]

Dear Erman,

we have dropped external redundancy diskgroup using below command,Our version 2node rac 12.1.0.2

Drop diskgroup test including contents;

Is there a way to get back the diskgroup?

Thank you

[ErmanArslansOracleBlog]

Maybe with amdu and kfed utilities.. But I haven't tested it yet..
It is advanced bytheway, and it is like a R&D..
But here there is an article -> https://externaltable.blogspot.com/2013/12/how-to-recover-files-from-dropped-asm.html

[satish]

Thanks erman.

Just want to understand even after dropping the diskgroup,still data will be present on disks?

because from the article,they are just changing the header from 4 to 3 and all the data is back

Thank you

[ErmanArslansOracleBlog]

Yes it seems..
Think about a diskgroup with 10TB disk drives
If the drop operation would overwrite all the blocks, then you should wait for days to complete the drop operation. So it makes sense + you can test it. (I send you the article already)..