Installation guide

Appendix F. Additional Boot Options 89
nopass
This command disables the passing of keyboard and mouse information to stage 2 of the instal-
lation program. It can be used to test keyboard and mouse configuration screens during stage 2
of the installation program when performing a network installation.
nopcmcia
This command ignores any PCMCIA controllers in system.
noprobe
This command disables hardware detection and instead prompts the user for hardware informa-
tion.
noshell
This command disables shell access on virtual console 2 during an installation.
nousb
This command disables the loading of USB support during the installation. If the installation
program tends to hang early in the process, this command may be helpful.
nousbstorage
This command disables the loading of the usbstorage module in the installation program’s loader.
It may help with device ordering on SCSI systems.
numa=off
Red Hat Enterprise Linux supports NUMA (Non-Uniform Memory Access) on the AMD64 ar-
chitecture. While all CPUs can access all memory even without NUMA support, the NUMA
support present in the updated kernel causes memory allocations to favor the CPU on which
they originate as much as possible, thereby minimizing inter-CPU memory traffic. This can pro-
vide significant performance improvements in certain applications. To revert to the original non-
NUMA behavior, specify this boot option.
reboot=b
This x86, AMD64, and Intel® EM64T boot command changes the way the kernel tries to reboot
the machine. If a kernel hang is experienced while the system is shutting down, this command
may cause the system to reboot successfully.
rescue
This command runs rescue mode. Refer to the Red Hat Enterprise Linux System Administration
Guide for more information about rescue mode.
resolution=
Tells the installation program which video mode to run. It accepts any standard resolution, such
as 640x480, 800x600, 1024x768, and so on.
serial
This command turns on serial console support.
skipddc
This x86 boot command skips the ddc monitor probe which causes problems on some systems.