bootlist Command

Commands Reference, Volume 1

bootlist Command

Purpose

Displays and alters the list of boot devices available to the system.

Syntax

bootlist [ { -m Mode } [ -r ] [ -o ] [ [ -i ] | [ [ -f File ] [ Device [ Attr=Value ... ] ... ] ] ]

Description

The bootlist command allows the user to display and alter the list of possible boot devices from which the system may be booted. When the system is booted, it will scan the devices in the list and attempt to boot from the first device it finds containing a boot image. This command supports the updating of the following:

Normal boot list. The normal list designates possible boot devices for when the system is booted in normal mode.
Service boot list. The service list designates possible boot devices for when the system is booted in service mode. How a system is booted in service mode is hardware-platform dependent. It may require a key switch to be turned to the Service position, a particular function key to be pressed during the boot process, or some other mechanism, as defined for the particular hardware platform.
Previous boot device entry. This entry designates the last device from which the system booted. Some hardware platforms may attempt to boot from the previous boot device before looking for a boot device in one of the other lists.

Support of these boot lists may vary from platform to platform. A boot list can be displayed or altered only if the platform supports the specified boot list. It may even be the case that a particular hardware platform does not support any of the boot lists.

When searching for a boot device, the system selects the first device in the list and determines if it is bootable. If no boot file system is detected on the first device, the system moves on to the next device in the list. As a result, the ordering of devices in the device list is extremely important.

The bootlist command supports the specification of generic device types as well as specific devices for boot candidates. Possible device names are listed either on the command line or in a file. Devices in the boot device list occur in the same order as devices listed on the invocation of this command.

The devices to be entered into the boot list may be specified in a file. This makes an alterable record of the boot devices available for reference or future update. When the -f flag is used, the list of devices is taken from the file specified by the file variable. Devices from this list are then placed in the boot list in the order found in the file.

Attention: Care must be taken in specifying the possible boot devices. A future reboot may fail if the devices specified in the device list become unbootable. The system must not be powered off or reset during the operation of the bootlist command. If the system is reset, or if power fails at a critical point in the execution of this command, the boot list may be corrupted or lost.

The selection of the boot list to display or alter is made with the -m mode option, where the mode variable is one of the keywords: service, normal, both, or prevboot. If the both keyword is specified, then both the normal boot list and the service boot list will be displayed, or if being altered, will be set to the same list of devices. If the prevboot keyword is specified, the only alteration allowed is with the -i (invalidate) flag . The -i flag invalidates the boot list specified by the -m flag.

In versions 4.2 and later, the devices currently in the boot list may be displayed by using the -o flag. The list of devices that make up the specified boot list will be displayed, one device per line. If a device specified in the boot list is no longer present on the system, a `-' is displayed instead of a name. The output is in a form that can be captured in a file and used as input to the bootlist command with the -f flag. This may be useful for restoring a boot list after making a temporary change.

Device Choices

The device name specified on the command line (or in a file) can occur in one of two different forms:

It can indicate a specific device by its device logical name.

It can indicate a generic or special device type by keyword. The following generic device keywords are supported:

fd	Any standard I/O-attached diskette drive
scdisk	Any SCSI-attached disk (including serial-link disk drives)
badisk	Any direct bus-attached disk
cd	Any SCSI-attached CD-ROM
rmt	Any SCSI-attached tape device
ent	Any Ethernet adapter
tok	Any Token-Ring adapter
fddi	Any Fiber Distributed Data Interface adapter

Note: Some hardware platforms do not support generic device keywords. If a generic device keyword is specified on such a platform, the update to the boot list is rejected and this command fails.

When a specific device is to be included in the device list, the device's logical name (used with system management commands) must be specified. This logical name is made up of a prefix and a suffix. The suffix is generally a number and designates the specific device. The specified device must be in the Available state. If it is not, the update to the device list is rejected and this command fails. The following devices and their associated logical names are supported (where the bold type is the prefix and the xx variable is the device-specific suffix):

fdxx	Diskette-drive device logical names
hdiskxx	Physical-volume device logical names
cdxx	SCSI CD-ROM device logical names
rmtxx	Magnetic-tape device logical names
entxx	Ethernet-adapter logical names
tokxx	Token-ring adapter logical names
fddixx	Fiber Distributed Data Interface adapter logical names

Attribute Choices

Attributes are extra pieces of information about a device that the user supplies on the command line. Since this information is specific to a particular device, generic devices do not have attributes. Attributes apply to the device that immediately precedes them on the command line, which allows attributes to be interspersed among devices on the command line. Currently, only network devices have attributes. These are:

bserver	IP address of the BOOTP server
gateway	IP address of the gateway
client	IP address of the client
hardware	Hardware address

These attributes can be combined in the following ways:

The hardware attribute cannot be specified alone; it must be specified with the bserver or gateway attribute. When specified with bserver or gateway, it applies to the server or gateway, respectively; when both bserver and gateway are specified, hardware will apply to gateway.
The bserver attribute can be specified alone, with hardware, and/or gateway.
If the gateway attribute is specified, bserver and client must also be specified.
The client attribute can only be specified with gateway and bserver.

Some of these attributes may not be supported on some hardware platforms. Additional hardware platform restrictions may apply.

The syntax for specifying an attribute is attr=value, where attr is the attribute name, value is the value, and there are no spaces before or after the =.

File Format When Using the -f Flag

The file specified by the file variable should contain device names separated by white space:

hdisk0 hdisk1 cd1

or one device per line:

hdisk0
hdisk1
cd1

Error Handling

If this command returns with an error, the device lists are not altered. The following device list errors are possible:

If the user attempts to display or alter a boot list that is not supported by the hardware platform, the command fails, indicating the mode is not supported.
If the user attempts to add too many devices to the boot list, the command fails, indicating that too many devices were requested. The number of devices supported varies depending on the device selection and the hardware platform .
If an invalid keyword, invalid flag, or unknown device is specified, the command fails with the appropriate error message.
If a specified device is not in the Available state, the command fails with the appropriate error message.

Flags

Device	Provides the names of the specific or generic devices to include in the boot list.
-f File	Indicates that the device information is to be read from the specified file name.
-i	Indicates that the device list specified by the -m flag should be invalidated.
-m Mode	Specifies which boot list to display or alter. Possible values for the mode variable are normal, service, both, or prevboot.
-o	Indicates that the specified boot list is to be displayed after any specified alteration is performed. The output is a list of device names. This flag applies only to AIX Version 4.2 or later.
-r	Indicates that the specified boot list is to be displayed after any specified alteration is performed. The output is hardware-platform dependent. It may be a hexadecimal dump of the boot list or a list of device names. (This is normally used for problem determination.)

Security

Privilege Control: Only the root user and members of the security group should have execute (x) access to this command.

Auditing Events:

Event	Information
NVRAM_Config	File name

Examples

To invalidate the Service mode boot list, enter:
```
bootlist -m service -i
```
To make a boot list for Normal mode with devices listed on the command line, enter:
```
bootlist -m normal hdisk0 hdisk1 rmt0 fd
```
To make a boot list for Normal mode with a device list from a file, enter:
```
bootlist -m normal -f /bootlist.norm
```
where bootlist.norm is a file containing device names to be placed in the boot list for Normal mode. The device names in the bootlist.norm file must comply with the described format.
To invalidate the previous boot device entry, enter:
```
bootlist -m prevboot
```
To boot from a Token-Ring device in slot 2, enter:
```
bootlist -m normal tok0
```

To attempt to boot through a gateway using Ethernet, and then try other devices, enter:

bootlist -m normal ent0 gateway=129.35.21.1 bserver=129.12.2.10
\ client=129.35.9.23 hdisk0 rmt0 tok0 bserver=129.35.10.19
hdisk1

Related Information

The nvram special file.

Device Configuration Subsystem Programming Introduction in AIX Kernel Extensions and Device Support Programming Concepts.

List of Device Configuration Commands in AIX Kernel Extensions and Device Support Programming Concepts.

Special Files Overview in AIX Version 4.3 Files Reference.