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Partition numbers

Within the package Boot-US all partitions on a disk are assigned a partition number according to the following rule:

For MBR partitions the primary and extended partitions are assigned always a partition number between 1 and 4. Logical partitions are assigned always a partition number of 5 and higher.

Within each of the two groups the partitions are ordered according to their position on the disk. For example a primary (or extended) partition with the number 1 lies before a partition with the number 2. Similarly a logical partition with the number 5 always lies before a log. partition with the number 6.

For GPT partitions the protective partition is assigned the partition number 0. The actual GPT partitions get a partition number starting with 1. The numbers are based on the position on the disk. Higher numbers lie further back.