Boot Parameters
Boot
parameters are specified using a three-part directive that includes
the name of the parameter and an optional list of options, which
consists of an equal sign
(=
) followed by
a comma-separated list of option values
No spaces may appear in the directive. As an example, the following directive specifies the identity of the Linux root partition:
root=/dev/hda1
The installation program generally refers to partitions by using labels, so that you can boot a system even if you move the partitions around. A root directive referring to a label looks like this:
root=LABEL=/usr
You can specify multiple directives by separating them with a space. For example, the following specifies the identity of the Linux root partition and that the root partition is initially mounted read-only, so that a thorough check of its filesystem can be performed:
root=/dev/hda1 ro
Most directives are interpreted by the kernel, though GRUB is also
capable of processing directives. If you specify a directive that
neither the kernel nor GRUB understands (assuming
you’re using GRUB), a directive that includes an
equal sign is passed to the init process as an
environment variable. You learned about environment variables in
Chapter 12. A nonkernel directive that
doesn’t include an equal sign is passed to the
init process. An example of this usage is
specifying the directive single
, which causes
init to start your system in single-user mode:
root=/dev/hda1 ro single
General Boot Arguments
Table C-2 describes ...
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