Using /etc/system to Modify Kernel Variables

The /etc/system file is read by the operating system kernel at start-up. It configures the search path for loadable operating system kernel modules and enables kernel variables to be set. For more information, see the man page for system(4).

Use the set commands in /etc/system carefully because the commands in /etc/system cause automatic patches of the kernel.

If your machine does not boot and you suspect a problem with /etc/system, use the boot -aoption. With this option, the system prompts (with defaults) for its boot parameters. One of these is the /etc/system configuration file. Either use the name of a backup copy of the original /etc/system file or /dev/null. Fix the file and immediately reboot the system to make sure it is operating correctly.