System Administration Guide: Devices and File Systems

Specifying Block Numbers to format Commands

Whenever you are required to specify a disk block number, there are two ways to do so:

You can specify the information as an integer that represents the logical block number. You can specify the number in any base, but the default is decimal. The maximum operator (a dollar sign, $) can also be used here so that format utility can select the appropriate value. Logical block format is used by the SunOS disk drivers in error messages.

The other way to specify a block number is by using cylinder/head/sector format. In this method, you must specify explicitly the three logical components of the block number: the cylinder, head, and sector values. These values are still logical. However, they allow you to define regions of the disk that are related to the layout of the media.

If any of the cylinder/head/sector numbers are not specified, the value is assumed to be zero. You can also use the maximum operator in place of any of the numbers. Then, the format utility will select the appropriate value. The following are some examples of cylinder, head, and sector values:

Enter defective block number: 34/2/3
Enter defective block number: 23/1/
Enter defective block number: 457//
Enter defective block number: 12345
Enter defective block number: Oxabcd
Enter defective block number: 334/$/2
Enter defective block number: 892//$

The format utility always displays block numbers in both formats. Also, the help facility shows you the upper and lower limits of the block number expected, in both formats.