How EDGINERS processing works

Before initializing or erasing a tape volume, DFSMSrmm verifies that the correct volume is mounted by reading any existing label, obtaining the volume serial number from the tape library vision system, or prompting the operator to confirm that the external label is correct. EDGINERS labels tape volumes as follows:

For standard label volumes, DFSMSrmm creates a standard volume label, an 80-byte dummy header label, and a tape mark.
A standard volume label with a serial number you specify and a blank security byte. The format of the ISO/ANSI label is constructed either for Version 3 or Version 4, depending on the options, of the label standard. For a complete description of IBM standard volume labels and ISO/ANSI Version 3 volume labels, see z/OS DFSMS Using Magnetic Tapes.
An 80-byte dummy header label. For IBM standard labels, this header consists of the characters HDR1 followed by zeros. For ISO/ANSI labels, this header consists of the characters HDR1 followed by zeros, with these exceptions:
- Position 54, which contains an ASCII space
- A 1 in the file section, file sequence, and generation number fields
- A leading space in the creation and expiration date fields
- A system code of IBMZLA, followed by 13 spaces, to identify the operating system creating the label
For tapes with no label, DFSMSrmm writes an 80-byte record that is not recognized as any valid label format, however, the DFSMSrmm utility can recognize it as an unlabeled tape once it is initialized.

The first time a tape that is labeled by EDGINERS is used for output, these sequence of events occurs:

The tape mark that EDGINERS created is overwritten.
The dummy header label that EDGINERS created is filled in with operating system data and device-dependent information.
A HDR2 record, containing data set characteristics, is created.
User header labels are written if exits to user label routines are provided.
A new tape mark is written.
Data is placed on the receiving volume.

When relabeling a volume defined to DFSMSrmm, DFSMSrmm uses the information recorded about the old volume as part of the new volume information recorded in the control data set.

This information is taken from the old volume record: Expiration Date, Density, Use Count, Store Id, Bin Number, Old Bin Number, Loan Location, Previous Location, Last Read and Write dates, Assigned Date and Time, Owner, Status, Label Type, Release actions, Actions Pending (excluding initialize and erase), Volume access and accessors, Unit name, Rack number, Temporary / Permanent Read / Write error counts.

When a volume that resides in an automated system-managed tape library is rejected at OPEN time because the tape media servo tracks require formatting, DFSMSrmm updates the volume information in the control data set. DFSMSrmm sets the volume INIT action to indicate that the volume must be initialized. If EDGINERS is used to relabel a volume and servo tracks have not been formatted, DFSMSrmm cannot initialize the volume.