General Parameters

debug=⟨0 | 1⟩

Enable debug mode.

break=⟨BREAKPOINT⟩

Specify breakpoint where shell should be invoked. Useful for debugging.

List of builtin breakpoints:

• boot

 

• root

 

Hooks can provide their own breakpoints. See source code of hooks for more information.

root=⟨UUID | LABEL | /dev/* | PARTUUID⟩

Specify which way initramfs will use to look up root filesystem.

UUID

Lookup device by uuid.

LABEL

Lookup device by label.

/dev/*

Lookup device by full path.

PARTUUID

Lookup device by partition uuid.

Initramfs must contain blkid utility for ability to use UUID, LABEL, PARTUUID. Note: PARTUUID only supported in util-linux' blkid(8).

root_type=⟨TYPE⟩

 

rootfstype=⟨TYPE⟩

Explicitly set root filesystem type. Kernel must support specified type.

rootdelay=⟨DELAY⟩

Specify maximum number of seconds to wait for root device instead of the default 30 seconds.

root_opts=⟨OPTS⟩

 

rootflags=⟨OPTS⟩

See fstab(5) fourth field.

Hooks Parameters

Initramfs must contain appropriate hooks for ability to use below parameters.

The parameters for LVM hook are as follows:

lvm_tag=⟨TAG⟩

Specify LVM tag which will be used to trigger LVM.

This option will be ignored if lvm_name/lvm_group was specified.

lvm_name=⟨NAME⟩

Specify LVM name which will be used to trigger LVM.

lvm_group (see below) must be specified.

lvm_group=⟨GROUP⟩

Specify LVM group which will be used to trigger LVM.

lvm_discard=⟨0 | 1⟩

Pass issue_discards to LVM. Leave empty to disable. Useful for SSD's.

The parameters for LUKS hook are as follows:

luks_name=⟨NAME⟩

Specify which name will be registered to mapping table after cryptsetup(8) unlocks LUKS root.

luks_root=⟨UUID | LABEL | /dev/* | PARTUUID⟩

See root (above) for details.

luks_discard=⟨0 | 1⟩

Pass “--allow-discards” to cryptsetup(8). Leave empty to disable.

Useful for SSD's, but you must know that security will be decreased.