Knowledge Base:Adjusting GRUB settings for a single boot session
When troubleshooting boot failures or trying to make changes for kernel settings, users might want to boot their system with a particular change in the GRUB bootloader configuration for a single boot session (i.e. not persistent).
Gentoo Linux systems using GRUB as the bootloader.
With GRUB, it is possible to boot with different settings for just a single boot session. Changes made herein are not persisted, so rebooting afterwards will boot back using the "old" configuration settings.
- During bootup, wait until the GRUB boot menu is displayed. The default timeout for GRUB is 30 seconds (if necessary press any key other than Enter or → to halt the timeout);
- Navigate to the entry desired boot from, but do not press the Enter key. Instead, press the E key (which stands for edit);
- Navigate to the line needed to be modified (which is most likely the one starting with
kernel, but can also be the
initrdline) and press E again to edit this specific line. When finished changing the line, press the Enter key;
- When all required changes have been made to the line(s), press the B key to boot the entry.
If happy with the result, do not forget to update /boot/grub/grub.conf with changes made in the steps above for persistent result.