System Administration Guide: Basic Administration

Chapter 35 The format Utility (Reference)

This chapter describes the format utility's menu and commands.

This is a list of the reference information in this chapter.

For a overview of when to use the format utility, see Chapter 31, Managing Disks (Overview).

Recommendations and Requirements for Using The format Utility

You must be superuser or a member of an equivalent role to use the format utility. If you are not superuser or have assumed an equivalent role, you will see the following error message when trying to use the format utility:


$ format
Searching for disks...done
No permission (or no disks found)!

Keep the following guidelines in mind when using the format utility and you want to preserve the existing data:

Format Menu and Command Descriptions

The format main menu looks like the following:


FORMAT MENU:
        disk       - select a disk
        type       - select (define) a disk type
        partition  - select (define) a partition table
        current    - describe the current disk
        format     - format and analyze the disk
        repair     - repair a defective sector
        label      - write label to the disk
        analyze    - surface analysis
        defect     - defect list management
        backup     - search for backup labels
        verify     - read and display labels
        save       - save new disk/partition definitions
        inquiry    - show vendor, product and revision
        volname    - set 8-character volume name
        quit
format> 

The following table describes the format main menu items.

Table 35–1 The format Main Menu Item Descriptions

Item 

Command or Menu? 

Description 

disk

Command 

Lists all of the system's drives. Also lets you choose the disk you want to use in subsequent operations. This disk is referred to as the current disk. 

type

Command 

Identifies the manufacturer and model of the current disk. Also displays a list of known drive types. Choose the Auto configure option for all SCSI-2 disk drives.

partition

Menu 

Creates and modifies slices. For more information, see The partition Menu.

current

Command 

Displays the following information about the current disk: 

  • Device name and device type

  • Number of cylinders, alternate cylinders, heads and sectors

  • Physical device name

format

Command 

Formats the current disk by using one of these sources of information in this order: 

  1. Information that is found in the format.dat file

  2. Information from the automatic configuration process

  3. Information that you enter at the prompt if there is no format.dat entry

fdisk

Menu 

IA platform only: Runs the fdisk program to create a Solaris fdisk partition.

repair

Command 

Repairs a specific block on the current disk. 

label

Command 

Writes a new label to the current disk. 

analyze

Menu 

Runs read, write, compare tests. For more information, see The analyze Menu.

defect

Menu 

Retrieves and prints defect lists. For more information, see The defect Menu.

backup

Command 

Searches for backup labels. 

verify

Command 

Prints the following information about the current disk: 

  • Device name and device type

  • Number of cylinders, alternate cylinders, heads and sectors

  • Partition table

save

Command 

Saves new disk and partition information. 

inquiry

Command 

Prints the vendor, product name, and revision level of the current drive (SCSI disks only). 

volname

Command 

Labels the disk with a new eight-character volume name. 

quit

Command 

Exits the format menu.

The partition Menu

The partition menu looks similar to the following:


format> partition
PARTITION MENU:
        0      - change `0' partition
        1      - change `1' partition
        2      - change `2' partition
        3      - change `3' partition
        4      - change `4' partition
        5      - change `5' partition
        6      - change `6' partition
        7      - change `7' partition
        select - select a predefined table
        modify - modify a predefined partition table
        name   - name the current table
        print  - display the current table
        label  - write partition map and label to the disk
        quit
partition> 

The following table describes the partition menu items.

Table 35–2 Descriptions for partition Menu Items

Sub-Command 

Description 

change `n' partition

Lets you specify the following information for the new slice: 

  • Identification tag

  • Permission flags

  • Starting cylinder

  • Size

select

Lets you choose a predefined slice table. 

modify

Lets you change all the slices in the slice table. This command is preferred over the individual change `x' partition commands.

name

Lets you specify a name for the current slice table. 

print

Displays the current slice table. 

label

Writes the slice map and the label to the current disk. 

quit

Exits the partition menu.

x86: The fdisk Menu

The fdisk menu appears on IA based systems only and looks similar to the following.


format> fdisk
             Total disk size is 1855 cylinders
             Cylinder size is 553 (512 byte) blocks
                                           Cylinders
      Partition   Status    Type      Start   End   Length    %
      =========   ======    ========  =====   ===   ======   ===
          1                 DOS-BIG       0   370     371     20
          2       Active    SOLARIS     370  1851    1482     80
 
SELECT ONE OF THE FOLLOWING:
     1.   Create a partition
     2.   Change Active (Boot from) partition
     3.   Delete a partition
     4.   Exit (Update disk configuration and exit)
     5.   Cancel (Exit without updating disk configuration)
Enter Selection: 

The following table describes the fdisk menu items.

Table 35–3 x86: Descriptions for fdisk Menu Items

Menu Item 

Description 

Create a partition

Creates an fdisk partition. You must create a separate partition for each operating environment such as Solaris or DOS. There is a maximum of 4 partitions per disk. You are prompted for the size of the fdisk partition as a percentage of the disk.

Change Active partition

Lets you specify the partition to be used for booting. This menu item identifies where the first stage boot program looks for the second stage boot program. 

Delete a partition

Deletes a previously created partition. This command destroys all the data in the partition. 

Exit

Writes a new version of the partition table and exits the fdisk menu.

Cancel

Exits the fdisk menu without modifying the partition table.

The analyze Menu

The analyze menu looks similar to the following.


format> analyze
 
ANALYZE MENU:
    read     - read only test   (doesn't harm SunOS)
    refresh  - read then write  (doesn't harm data)
    test     - pattern testing  (doesn't harm data)
    write    - write then read      (corrupts data)
    compare  - write, read, compare (corrupts data)
    purge    - write, read, write   (corrupts data)
    verify   - write entire disk, then verify (corrupts data)
    print    - display data buffer
    setup    - set analysis parameters
    config   - show analysis parameters
    quit
analyze> 

The following table describes the analyze menu items.

Table 35–4 Descriptions for analyze Menu Item

Sub-Command 

Description 

read

Reads each sector on the current disk. Repairs defective blocks as a default. 

refresh

Reads then writes data on the current disk without harming the data. Repairs defective blocks as a default. 

test

Writes a set of patterns to the disk without harming the data. Repairs defective blocks as a default. 

write

Writes a set of patterns to the disk then reads the data on the disk back. Destroys existing data on the disk. Repairs defective blocks as a default. 

compare

Writes a set of patterns to the disk, reads the data back, and then compares it to the data in the write buffer. Destroys existing data on the disk. Repairs defective blocks as a default. 

purge

Removes all data from the disk so that the data can't be retrieved by any means. Data is removed by writing three distinct patterns over the entire disk (or a section of the disk). If the verification passes, a hex-bit pattern is written over the entire disk (or a section of the disk). 

Repairs defective blocks as a default. 

verify

Writes unique data to each block on the entire disk in the first pass. Reads and verifies the data in the next pass. Destroys existing data on the disk. Repairs defective blocks as a default. 

print

Displays the data in the read/write buffer. 

setup

Lets you specify the following analysis parameters: 

Analyze entire disk? yes
Starting block number: depends on drive
Ending block number: depends on drive
Loop continuously? no
Number of passes: 2
	Repair defective blocks? yes
Stop after first error? no
Use random bit patterns? no
Number of blocks per transfer: 126 (0/n/nn)
Verify media after formatting? yes
Enable extended messages? no
Restore defect list? yes
Restore disk label? yes

Defaults are shown in bold. 

config

Displays the current analysis parameters. 

quit

Exits the analyze menu.

The defect Menu

The defect menu looks similar to the following:


format> defect
 
DEFECT MENU:
        primary  - extract manufacturer's defect list
        grown    - extract manufacturer's and repaired defects lists
        both     - extract both primary and grown defects lists
        print    - display working list
        dump     - dump working list to file
        quit
defect> 

The following table describes the defect menu items.

Table 35–5 The defect Menu Item Descriptions

Sub-Command 

Description 

primary

Reads the manufacturer's defect list from the disk drive and updates the in-memory defect list. 

grown

Reads the grown defect list, which are defects that have been detected during analysis, and then updates the in-memory defect list. 

both

Reads both the manufacturer's defect list and the grown defect list, and then updates the in-memory defect list. 

print

Displays the in-memory defect list. 

dump

Saves the in-memory defect list to a file. 

quit

Exits the defect menu.

The format.dat File

The format.dat file that is shipped with the Solaris operating environment supports many standard disks. If your disk drive is not listed in the format.dat file, you can choose to add an entry for it or adding entries with the format utility by selecting the type command and choosing the other option.

Adding an entry to the format.dat file can save time if the disk drive will be used throughout your site. To use the format.dat file on other systems, copy the file to each system that will use the specific disk drive that you added to the format.dat file.

You should modify the /etc/format.dat file for your system if you have one of the following:


Note –

Do not alter default entries in the /etc/format.dat file. If you want to alter the default entries, copy the entry, give it a different name, and make the appropriate changes to avoid confusion.


Contents of the format.dat File

The format.dat contains specific disk drive information that is used by the format utility. Three items are defined in the format.dat file:

Syntax of the format.dat File

The following syntax rules apply to the /etc/format.dat file:

Keywords in the format.dat File

The format.dat file contains disk definitions that are read by the format utility when it is started. Each definition starts with one of the following keywords: disk_type or partition. These keywords are described in the following table.

Table 35–6 Keyword Descriptions for the format.dat File

Keyword 

Use 

disk_type

Defines the controller and disk model. Each disk_type definition contains information that concerns the physical geometry of the disk. The default data file contains definitions for the controllers and disks that the Solaris operating environment supports.

You need to add a new disk_type only if you have an unsupported disk. You can add as many disk_type definitions to the data file as you want.

partition

Defines a slice table for a specific disk type. The slice table contains the slice information, plus a name that lets you refer to it in the format utility. The default format.dat file contains default slice definitions for several kinds of disk drives. Add a slice definition if you recreated slices on any of the disks on your system. Add as many slice definitions to the data file as you need.

Disk Type (format.dat)

The disk_type keyword in the format.dat file defines the controller and disk model. Each disk_type definition contains information about the physical geometry of the disk. The default format.dat file contains definitions for the controllers and disks that the Solaris operating environment supports. You need to add a new disk_type only if you have an unsupported disk. You can add as many disk_type definitions to the data file as you want.

The keyword itself is assigned the name of the disk type. This name appears in the disk's label, and is used to identify the disk type whenever the format utility is run. Enclose the name in double quotation marks to preserve any white space in the name. The following table describes the identifiers that must also be assigned values in all disk_type definitions.

Table 35–7 Required disk_type Identifiers

Identifier 

Description 

ctlr

Identifies the controller type for the disk type. Currently, the supported values are SCSI and ATA.  

ncyl

Specifies the number of data cylinders in the disk type. This determines how many logical cylinders of the disk the system will be allowed to access.  

acyl

Specifies the number of alternate cylinders in the disk type. These cylinders are used by the format utility to store information such as the defect list for the drive. You should always leave at least two cylinders for alternates.

pcyl

Specifies the number of physical cylinders in the disk type. This number is used to calculate the boundaries of the disk media. This number is usually equal to ncyl plus acyl.

nhead

Specifies the number of heads in the disk type. This number is used to calculate the boundaries of the disk media.  

nsect

Specifies the number of data sectors per track in the disk type. This number is used to calculate the boundaries of the disk media. Note that this is only the data sectors. Any spares are not reflected in the number of data sections per track.  

rpm

The rotations per minute of the disk type. This information is put in the label and later used by the file system to calculate the optimal placement of file data.  

Other identifiers might be necessary, depending on the controller. The following table describes the identifiers that are required for SCSI controllers.

Table 35–8 disk_type Identifiers for SCSI Controllers

Identifier 

Description 

fmt_time

A number that Indicates how long it takes to format a given drive. See the controller manual for more information.  

cache

A number that controls the operation of the on-board cache while the format utility is operating. See the controller manual for more information.

trks_zone

A number that specifies how many tracks you have per defect zone, to be used in alternate sector mapping. See the controller manual for more information.  

asect

A number that specifies how many sectors are available for alternate mapping within a given defect zone. See the controller manual for more information.  

The following are examples of disk_type definitions:


disk_type = "SUN1.3G" \
        : ctlr = SCSI : fmt_time = 4 \
        : trks_zone = 17 : asect = 6 : atrks = 17 \
        : ncyl = 1965 : acyl = 2 : pcyl = 3500 : nhead = 17 : nsect = 80 \
        : rpm = 5400 : bpt = 44823

disk_type = "SUN2.1G" \
        : ctlr = SCSI : fmt_time = 4 \
        : ncyl = 2733 : acyl = 2 : pcyl = 3500 : nhead = 19 : nsect = 80 \
        : rpm = 5400 : bpt = 44823

disk_type = "SUN2.9G" \
        : ctlr = SCSI : fmt_time = 4 \
        : ncyl = 2734 : acyl = 2 : pcyl = 3500 : nhead = 21 : nsect = 99 \
        : rpm = 5400

Partition or Slice Tables (format.dat)

A partition table in the format.dat file defines a slice table for a specific disk type.

The partition keyword in the format.dat file is assigned the name of the slice table. Enclose the name in double quotation marks to preserve any white space in the name. The following table describes the identifiers that must be assigned values in all slice tables.

Table 35–9 Required Identifiers for Slice Tables

Identifier 

Description 

disk

The name of the disk_type that this slice table is defined for. This name must appear exactly as it does in the disk_type definition.

ctlr

The disk controller type that this slice table can be attached to. Currently, the supported values are ATA for ATA controllers and SCSI for SCSI controllers. The controller type that is specified here must also be defined for the disk_type that you specified in the disk_type definition.

The other identifiers in a slice definition describe the actual slice information. The identifiers are the numbers 0 through 7. These identifiers are optional. Any slice that is not explicitly assigned is set to 0 length. The value of each of these identifiers is a pair of numbers separated by a comma. The first number is the starting cylinder for the slice, and the second is the number of sectors in the slice. The following are some examples of slice definitions:


partition = "SUN1.3G" \
        : disk = "SUN1.3G" : ctlr = SCSI \
        : 0 = 0, 34000 : 1 = 25, 133280 : 2 = 0, 2672400 : 6 = 123, 2505120

partition = "SUN2.1G" \
        : disk = "SUN2.1G" : ctlr = SCSI \
        : 0 = 0, 62320 : 1 = 41, 197600 : 2 = 0, 4154160 : 6 = 171, 3894240

partition = "SUN2.9G" \
        : disk = "SUN2.9G" : ctlr = SCSI \
        : 0 = 0, 195426 : 1 = 94, 390852 : 2 = 0, 5683986 : 6 = 282, 5097708

Specifying an Alternate Data File for the format utility

The format utility learns of the location of an alternate file by the following methods.

  1. If a file name is given with the format -x option, that file is always used as the data file.

  2. If the -x option is not specified, then the format utility looks in the current directory for a file named format.dat. If the file exists, it is used as the data file.

  3. If neither of these methods yields a data file, the format utility uses the /etc/format.dat file as the data file. This file is shipped with the Solaris operating environment and should always be present.

Rules for Input to format Commands

When you use the format utility, you need to provide various kinds of information. This section describes the rules for this information. For information on using format's help facility when you enter data, see Getting Help on the format Utility.

Specifying Numbers to format Commands

Several places in the format utility require an number as input. You must either specify the data or select a number from a list of choices. In either case, the help facility causes format to print the upper and lower limits of the number expected. Simply enter the number desired. The number is assumed to be in decimal format unless a base is explicitly specified as part of the number (for example, 0x for hexadecimal).

The following are examples of integer input:


Enter number of passes [2]: 34 
Enter number of passes [34] Oxf 

Specifying Block Numbers to format Commands

Whenever you are required to specify a disk block number, there are two ways to enter the information:

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 to let the format utility 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 the cylinder/head/sector designation. 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, but 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 and let the format utility select the appropriate value. The following are some examples of cylinder, head, and sector entries:


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 prints block numbers, in both formats. Also, the help facility shows you the upper and lower bounds of the block number expected, in both formats.

Specifying format Command Names

Command names are needed as input whenever the format utility displays a menu prompt. You can abbreviate the command names, as long as what you enter is sufficient to uniquely identify the command desired.

For example, use p to enter the partition menu from the format menu. Then, enter p to display the current slice table.


format> p
PARTITION MENU:
        0      - change `0' partition
        1      - change `1' partition
        2      - change `2' partition
        3      - change `3' partition
        4      - change `4' partition
        5      - change `5' partition
        6      - change `6' partition
        7      - change `7' partition
        select - select a predefined table
        modify - modify a predefined partition table
        name   - name the current table
        print  - display the current table
        label  - write partition map and label to the disk
        quit
partition> p

Specifying Disk Names to format Commands

There are certain times in the format utility when you must name something. In these cases, you are free to specify any string you want for the name. If the name has white space in it, the entire name must be enclosed in double quotation marks ("). Otherwise, only the first word of the name is used.

For example, if you want to identify a specific partition table for a disk, you can use the name sub-command available from the partition menu:


partition> name
Enter table name (remember quotes): "new disk3"

Getting Help on the format Utility

The format utility provides a help facility that you can use whenever the format utility is expecting input. You can request help about what input is expected by entering a question mark (?). The format utility displays a brief description of what type of input is needed.

If you enter a ? at a menu prompt, a list of available commands is displayed.

The man pages associated with the format utility include the following: