红帽全球峰会第 4 章 Configuring kernel command-line parameters
With kernel command-line parameters, you can change the behavior of certain aspects of the Red Hat Enterprise Linux kernel at boot time. As a system administrator, you control which options get set at boot. Note that certain kernel behaviors can only be set at boot time.
Changing the behavior of the system by modifying kernel command-line parameters can have negative effects on your system. Always test changes before deploying them in production. For further guidance, contact Red Hat Support.
4.1. What are kernel command-line parameters
With kernel command-line parameters, you can overwrite default values and set specific hardware settings. At boot time, you can configure the following features:
- The Red Hat Enterprise Linux kernel
- The initial RAM disk
- The user space features
By default, the kernel command-line parameters for systems using the GRUB boot loader are defined in the boot entry configuration file for each kernel boot entry.
You can manipulate boot loader configuration files by using the grubby utility. With grubby, you can perform these actions:
- Change the default boot entry.
- Add or remove arguments from a GRUB menu entry.
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