RE: Erasing DASD-decommission an AS400/iSeries/System i

Perform a DUMPOBJ against a user profile.  User profiles can hold a lot
of information that get deleted when you delete the profile.  User
Profile object can be very large.  I would un-install all software
except the base OS, delete all user profiles you can, including Q*
profiles.  Create as many jobs writing to files as necessary to crash
your system.  Re-boot and run the record update program to wipe your
data.  Now do the scratch install of the OS, say 5 times.  Once you have
the basic OS installed, Repeat.

Christopher Bipes
Information Services Director
CrossCheck, Inc.


-----Original Message-----

Jim Franz wrote:

Just a guess, but deleting profiles would delete the msgq with each

user, 

and that may be your space. I thought somewhere way back (maybe 310

days) 

IBM changed how user profiles stored after someone posted a

description of 

its location. Just don't know if profile info in what we call a

"file". If I 

remove data from some sort of space, is that area given back for

re-use or 

is it still allocated to the space?

User profiles can own objects and using DLTUSRPRF ... OWNOBJOPT(*DLT)
could delete a lot of stuff.  User profiles are MI objects, but there
may be user related information stored in files in QUSRSYS.  I think the
IBM changes you mention are related to where password information is
stored. It was moved to an internal machine (below MI) location.

Forgetting the hype and made up facts of today's forensic tv shows, I

know

data has been retreivable from disks & tape after fires, water damage,

and 

intentional efforts to destroy the drive.

Yes, assuming you have the right equipment.  Even retrieving data that
has been written over with a 1 pass erase program is specialty stuff.

Unless you have truly have sensitive or valuable information worth going
after by someone with the above, just filling DASD with a 1 pass version
of Larry's program should be sufficient to stop most retrieval attempts
(dumping disks).

If you want to go further, completely erase all the drives using another
system.  A PC with an compatible SCSI card should work.  Unfortunately
AFAIK, you can't boot a PPC64 linux (non-LPAR) from a CD/DVD on a system
i or this would be the way to go.  IBM could of course provide an erase
tool either via CD, DST or possibly the HMC.