Re: DOD wipe of disks in a virtual environment.

[DrFranken <midrange@xxxxxxxxxxxx>]

Rob,

	I actually created a program that writes very long (32K I think) 
records to a table that are binary patterns.  Options are 00000000 
11111111 10101010 and 01010101 or you can supply a hex number.  It 
writes until the disk is full then deletes the file and does the next 
pattern. In testing it was much quicker to delete and write new than it 
was to write once and then update during subsequent passes. MUCH.

	Issues with this are:

 1) Wherever the O/S is the O/S still is. We don't re-write those 
areas. Same with the program itself and other program space etc. You 
could in theory move some of this by removing disks from the ASP and 
then adding them back in without balancing but you still have the LIC on 
the load source and that doesn't move.

 2) To be even close to effective the system needs to be as bare as 
possible. Deleting every journal reciever, user profile, device 
description, output queue, IFS directory, LPP, etc etc. RCLSPLSTG, IPL 
to release temp space and run in restricted state at the console. But 
then it takes bloody forever. I run multiple jobs in batch until the 
disks are crying uncle.

 3) You'll never get anyone to accept this is 'good enough' unless they 
understand i in the first place. And then if they do understand i then 
they know that simply IPLing the I_BASE_01 disk, ending any RAID or 
mirroring and initializing all the disks is gonna be 'good enough' 
already. It really is. Really. Not kidding.

  But then there is this virtual environment where disks are no longer 
disks and the fog set in.....

        - Larry "DrFranken" Bolhuis

www.Frankeni.com
www.iDevCloud.com - Personal Development IBM i timeshare service.
www.iInTheCloud.com - Commercial IBM i Cloud Hosting.

On 8/28/2015 7:32 AM, rob@xxxxxxxxx wrote:
> Nathan,
>
> Try this
> CRTNWSSTG NWSSTG(DELETEME) NWSSIZE(2) FORMAT(*OPEN)
> CRTNWSD NWSD(DELETEME) RSRCNAME(*AUTO) TYPE(*GUEST *OPSYS) ONLINE(*NO)
> PARTITION(DELETEME)
> VRYCFG CFGOBJ(DELETEME) CFGTYPE(*NWS) STATUS(*ON)
> WRKNWSSTG
>
> Now, show me how you're going to do the following on that disk
> <snip>
>  From what I gather, you use a utility which purges all files, then writes
> perhaps many more files to fill up "every sector". Repeat the process 3
> times, then do a final purge.
> </snip>
>
>
> Rob Berendt