topic Re: How can I tell if dd(1) is finished? in Operating System - HP-UX

How can I tell if dd command is finished? Goes on forever.

kippstor — Fri, 13 May 2016 17:33:46 GMT

Hello,

I am currently trying to wipe disks by zeroing them out with dd. I have hp-ux and AIX machines. The hp-ux machines I boot off disk 1 cd Base Operating Environment where i stop the boot and load some commands to create /dev/zero and mknod /dev/zero c 3 0x000004

Then I run the following command

dd if=/dev/zero of=/dev/rdsk/c0t1d0

It runs forever - how can i tell if it worked? Other OSs finish within a couple of hours.

This is HP9000 rp3440 and rx2660

Thanks!

Re: How can I tell if dd command is finished? Goes on forever.

Steven Schweda — Fri, 13 May 2016 21:25:43 GMT

> It runs forever [...]

I know nothing, but a quick Web search (for keyworks like: erase disk
dd hp-ux) found a similar complaint:

http://community.hpe.com/t5/x/x/td-p/3696734

The responses there included a suggestion to use a non-default (big)
block size: "bs=1024k".

> [...] how can i tell if it worked?

Dump out some data from (near the end of) the disk before and after,
and see if any of them change from non-zero to zero? (If necessary,
write some non-zero data there first.)

Re: How can I tell if dd(1) is finished?

Dennis Handly — Sat, 14 May 2016 14:03:32 GMT

You could use tusc(1) to see if it is still moving.

And lsof(1) to see what the file pointer is.

But as Steven said, you need large block sizes.