boot(F)

Format

Description

Two distinct copies of /etc/default/boot exist; in the root filesystem and on the boot filesystem, /stand. (This permits /etc/default/boot to be read by programs that run from the boot filesystem before the kernel has loaded.) The copy on /stand is named /etc/default/boot (the slashes actually form part of the filename), while the main copy is named boot and is stored in /etc/default. /etc/default/boot is copied to /stand/etc/default/boot whenever the system makes an orderly shutdown, so that any changes are loaded at the next reboot.

All keywords and aliases boot recognizes are in the form:

name [ = ] value

If no = is used, one or more tabs or spaces should separate the name from the value. An = separating name from value may be preceded or followed by spaces and tabs. Programs other than boot which read the defaults file require the = and do not allow spaces or tabs.

The keywords boot recognizes include:

standalone=definition

boot checks to see if the entered standalone command is defined (or ``aliased'') in the defaults file; if it is, its definition is substituted for the entered standalone command, with any entered arguments appended to the end.

For example, if boot was loaded from the hard disk (hd(40)) and the entered command was:

test mem=1m-12m

and test is aliased as:

test  /etc/conf/cf.d/unix prompt="Ready? "

then the result bootstring is:

hd(40)/etc/conf/cf.d/unix prompt="Ready? " mem=1m-12m

By convention, standalone aliases (including defbootstr) are lowercase and keywords are uppercase, but boot will recognize both aliases and keywords in either case. (However, the case of the values, such as YES and NO, must be uppercase.)

ALTDEF=defaults

The file defaults, if it exists, is used instead as the default file (for boot). This process is repeated up to 100 times.

apm.cmd=arg

Configure any BIOS-APM present. See apm(HW) for details.

AUTOBOOT=YES or NO

If YES, boot automatically loads the UNIX system kernel as per the defbootstr setting after waiting for input for the time specified by TIMEOUT. The default is NO.

BOOTMNT=RO or RW or NO

If RO is used, mount the boot filesystem read only; this is the default setting. If RW is specified, the boot filesystem is read-write. If NO is specified, the boot filesystem is not mounted.

defbootstr=standalone arguments ...

The standalone program to run (with optional arguments) when only <Enter> is pressed or when AUTOBOOT=YES and nothing is entered within TIMEOUT seconds.

PWRCHECK=Y or N

Applies only to some machines equipped with a built-in uninterruptible power supply (UPS): if Y, checks the mains and battery condition; if the battery is low or the mains power has failed, warns that the system probably should not be booted. Default is N; note that this option applies only to a few machines and almost all available systems cannot use this facility. If the machine has a BIOS-APM, the apm.cmd= keyword should be used.

RONLYROOT=YES or NO

Whether or not the root filesystem is mounted readonly. This must be used only during installation, and not for a normal boot. It will effectively prevent writing to the filesystem.

SERIAL=param1, param2, ...

List of parameters specifying the baud rate, character size, parity, and number of stop bits of the serial console (SYSTTY=1). The params are the same as for the kernel.systty bootstring argument. Please see bootstring(HW) for details, including the default values.

SYSTTY=digit

If digit is 0, the system console is the display adapter; if 1, the system console is COM1. Please see bootstring(HW) for details, including the default console search procedure.

TIMEOUT=n

How many seconds to wait for input after the first prompt before assuming an answer of <Enter> (this causes defbootstr to be used). Applies only when AUTOBOOT is YES; the default is 60 seconds.

DEFAULT_LEVEL=n

The run-level to enter when leaving single-user mode.

FSCKFIX=YES or NO

Controls whether or not fsck(ADM) fixes any root filesystem problems by itself. If set to YES (default) and AUTOBOOT is YES (also default), then fsck is run on the root filesystem and all fixes are made automatically.

INHIBIT=n

If an inittab entry is respawned SPAWN_LIMIT times within SPAWN_INTERVAL seconds, init will not try to respawn that entry for this many seconds (unless a ``telinit q'' is done). The default value is 300 seconds (five minutes).

MAPKEY=YES or NO

Sets whether or not init invokes mapkey to configure console keyboard mapping; if not set, default is YES.

MULTIUSER=YES or NO

Sets whether or not init invokes sulogin or proceeds to multiuser mode.

PANICBOOT=YES or NO

Whether or not the system reboots after a panic; default is NO.

SERIAL8=YES or NO

Sets whether or not init allows the use of 8-bit characters (no parity) on a console configured over a serial line; if not set, default is NO.

SLEEPTIME=n

Sets the number n of seconds that init waits between checking th inittab file for changes. The default value is 0 (zero), suppressing this periodic examination. The kernel process bdflush writes cached changes to disk at BDFLUSHR intervals specified in the mtune(F) file

SPAWN_INTERVAL=n

If an inittab entry is respawned SPAWN_LIMIT times within this amount of time (seconds), init will not try to respawn that entry for INHIBIT seconds (unless a ``telinit q'' is done). The default value is 120 seconds.

SPAWN_LIMIT=n

If an inittab entry is respawned this many times within SPAWN_INTERVAL seconds, init will not try to respawn that entry for INHIBIT seconds (unless a ``telinit q'' is done). The default value is 10 attempts.

See also