IBM pSeries 615 Model 6C3, User Manual

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Format Media
This task allows the selection of diskettes, hardfiles, or optical media to be formatted. Each selection is
described below.
Hardfile Attached to SCSI Adapter (non-RAID)
v Hardfile Format
Writes all of the disk. The pattern written on the disk is device-dependent; for example some drives may
write all 0s, while some may write the hexadecimal number 5F. No bad block reassignment occurs
v Hardfile Format and Certify
Performs the same function as Hardfile Format. After the format is completed, Certify is run. Certify then
reassigns all bad blocks encountered.
v Hardfile Erase Disk
This option can be used to overwrite (remove) all data currently stored in user-accessible blocks of the
disk. The
Erase Disk option writes one or more patterns to the disk. An additional option allows data in
a selectable block to be read and displayed on the system console.
To use the Erase Disk option, specify the number (0-3) of patterns to be written. The patterns are
written serially; that is, the first pattern is written to all blocks. The next pattern is written to all blocks,
overlaying the previous pattern. A random pattern is written by selecting the
Write Random Pattern?
option.
Note: The Erase Disk service aid has not been certified as meeting the Department of Defense or any
other organization’s security guidelines.
To overwrite the data on the drive, use the following steps :
1. Select
Erase Disk .
2. Do a format without certify.
3. Select
Erase Disk to run it a second time.
For a newly installed drive, you can ensure that all blocks on the drive are overwritten with your pattern
by using the following procedure:
1. Format the drive.
2. Check the defect MAP by running the Erase Disk option.
Note: If you use the Format and Certify option, there may be some blocks which get placed into
the grown defect MAP.
3. If there are bad blocks in the defect MAP, record the information presented and ensure that this
information is kept with the drive. This data is used later 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
option which was used in step 2.
Note: Using the same version of the service aid is only critical if any bad blocks were found in step
3.
6. Compare the bad blocks which were recorded for the drive in step 3 with those that now appear in
the grown defect MAP.
Note: If there are differences between the saved data and the newly obtained data, all sectors on
this drive cannot be overwritten. The new bad blocks are not overwritten.
7. If the bad block list is the same, continue running the service aid to overwrite the disk with the
chosen pattern(s).
Chapter 7. Introducing Tasks and Service Aids
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