This shows you the differences between two versions of the page.
Next revision | Previous revision | ||
linux:linux_boot_order [2024/09/21 21:57] manu created |
linux:linux_boot_order [2024/09/22 21:43] (current) manu [Grub] |
||
---|---|---|---|
Line 5: | Line 5: | ||
Initial RAM disk (initrd or Initramfs) is a RAM filesystem mounted at startup to initialize kernel modules. | Initial RAM disk (initrd or Initramfs) is a RAM filesystem mounted at startup to initialize kernel modules. | ||
+ | ===== Initrd ===== | ||
+ | |||
+ | Rebuild initrd | ||
+ | <cli prompt='#'> | ||
+ | # dracut -f | ||
+ | </cli> | ||
+ | |||
+ | Another example to add multipathing | ||
+ | <cli prompt='#'> | ||
+ | # dracut --force --add multipath | ||
+ | </cli> | ||
+ | |||
+ | **Regenerating the initramfs** | ||
+ | * Adding Drivers Because of Hardware Changes | ||
+ | * Moving System Directories to a RAID or LVM | ||
+ | * Adding Disks to an LVM Group or Btrfs RAID Containing the Root File System | ||
+ | * Changing Kernel Variables (sysctl) | ||
+ | * Adding or removing swap devices, re-creating swap area, it required also to recreate grub | ||
You can read the content of initrd | You can read the content of initrd | ||
Line 17: | Line 35: | ||
# cp /boot/initrd.img . | # cp /boot/initrd.img . | ||
# unmkinitramfs initrd.img . | # unmkinitramfs initrd.img . | ||
+ | </cli> | ||
+ | |||
+ | ===== Grub ===== | ||
+ | |||
+ | Generate a new grub.cfg on BIOS based server | ||
+ | <cli prompt='#'> | ||
+ | # grub2-mkconfig -o /boot/grub2/grub.cfg | ||
+ | </cli> | ||
+ | |||
+ | Generate a new grub.cfg on UEFI based server | ||
+ | <cli prompt='#'> | ||
+ | # grub2-mkconfig -o /boot/efi/EFI/redhat/grub.cfg | ||
+ | </cli> | ||
+ | |||
+ | Check the syntax of grub.cfg | ||
+ | <cli prompt='#'> | ||
+ | # grub2-script-check /boot/grub2/grub.cfg | ||
</cli> | </cli> |