IBM RS/6000 7025 manual Version Erase

patterns

to

the

disk.

An additional

option allows data in a selectable block to

read

and

displayed

on

the

system

console.

To use the Erase Disk

option, specify the

number

(0-3) of patterns to

be

wri

Select

the

patterns

to

be

written;

the patterns are written serially. That is,

first pattern is written to all blocks. Then

the next pattern is written

to

all

overlaying

the

previous

pattern. A random pattern is written by selecting the

"Write

random

pattern?"

option.

The Erase

Disk

service

aid has not been certified as meeting the Department

Defense

or

any

other

organizations

security guidelines. The following steps

should

be

followed

if

the

data on

the drive is

to be overwritten:

1. Run the "Erase Disk" Service Aid to overwrite the data on the drive.

2. Do a format without certify.

3. Run a second pass of the erase service aid.

For a newly installed drive, you can insure that all blocks on the drive will b overwritten with your pattern if you use the following procedure:

1. Format the drive.

2. Check the defect map by running the Erase Disk Service Aid.

Note:

If

you use

the

"Format and

Certify"

option,

there

may

be some

block

which

get

placed

into the grown defect map.

3. If

there

are

bad blocks

in

the

defect

map, record

the

information

pres

and

ensure

that

this

information

is

kept with the

drive. This

data is

used

when

the

drive

is

to

be

overwritten.

4. Use the drive as you would normally.

5. When

the drive is no longer needed

and

is

to

be

erased, run the

same

version

of

the

Erase

Disk

Service Aid

which

was used in step 2.

Note:

Using

the

same

version

of

the

service

aid

is

only

critical

if

there

any

bad

blocks

found

in

step

3.

6. Compare

the

bad

blocks

which

were

recorded

with the drive in step

3

wit

those

which

now

appear

in

the

grown

defect

map.

Note:

If there are differences between the saved data and the newly

obtained data, then all of the sectors on this drive cannot be

overwritten. The new bad blocks

will

not

be

overwritten.

7. If

the bad block list is

the

same,

continue

running

the

service

aid

to

o

the

disk

with

the chosen

pattern(s).

Chapter 7. Using the Service7-11Aids