dd read error: Invalid argument

[Siddharth Tuli]

Hi

I ran dd on a DVD drive, on its dsf's showm in ioscan o/p. dd completes after some time, but it says "dd read error: Invalid argument" in the output.
_________________
# dd if=/dev/rdsk/c5t2d0 of=/dev/null bs=2048
dd read error: Invalid argument
7545+0 records in
7545+0 records out
#


# dd if=/dev/dsk/c5t2d0 of=/dev/null (default 512 bs)

dd read error: Invalid argument
30176+0 records in
30176+0 records out
#
________________

However, I found out there are 7545 blocks in the disk. And thus, this error is only after reading all the disk blocks.

What does this "dd read error" signify ?
Does this mean the disk has gone bad ?

Thanks
Siddharth

[Prashanth.D.S]

Hi Siddharth,

Yes most defntly this disk is gone bad you may think of replacing it very soon..

Best Regards,
Prashanth

[Steven E. Protter]

Shalom,

The disk is dead.

Long live its replacement.

SEP

[Siddharth Tuli]

Thank you.

But is there any reason as to why this error is shown after all the blocks are read ? I have also seen this on a couple of more disks, where the error appears only after all the blocks are read.

Thanks
Siddharth