Partition 1; Partition 0; Initialization Of Partitioned Tapes - Seagate STD124000N Product Manual

Tape Formats
Product Manual

Partition 1

The total number of frames in Partition 1 is recorded in the system log of Partition 1.
The virtual end of tape (VEOT) is a reference point for Partition 1, the same as the
PEOT on a single data space tape. The VEOT is found 450 frames before the
partition boundary.
The Partition 1 early warning point (EWP) functions the same as the EWP for a
single data space tape except that the EWP is not less than 3,067 frames
(approximately 500 mm) before the VEOT.
Partition 1's Data Area is followed by the Partition 1 EOD Area . The EOD Area can
be up to 450 frames in length and consist of tape-management frames, beginning
after the last amble in the sequence of amble frames following the last recorded
data group.
In the event that the end of the EOD area occurs before the VEOT, it is followed by
a post-EOD area extending to VEOT.

Partition 0

Immediately following Partition 1's VEOT, and after Partition 1's EOD frames,
Partition 0 begins with its LBOT. The LBOT is the partition boundary. The first frame
after this point has the absolute frame number (AFN) of 1.
The composition of Partition 0 is virtually the same as Partition 1.

Initialization of Partitioned Tapes

If a new or bulk-erased tape is used as a partitioned tape, we recommend that you
perform an initialization pass first. Given the fact that the user data may only fill one
partition, leaving the other empty, the initialization process ensures that the partition
boundary is correctly set, and Partition 1 and Partition 0 are both set up correctly
during the first write pass.
By definition, an Empty Partition 1 consists of:
z
A reference area
z
A system area
z
A data area, comprising a vendor group and at least 35 amble frames
z
A minimum of 3,517 tape-management frames identical to those of the EOD
area of Partition 1.
The vendor group preamble, the data area and the subsequent tape-management
frames all form a continuum extending to the partition boundary. No unrecorded
space, physical discontinuity, seam, absolute frame number discontinuity or
absolute frame number repetition is permitted.
Chapter 6
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