UPDATE-INITRAMFS(8) System Administration UPDATE-INITRAMFS(8)
NAME
update-initramfs - generate an initramfs image
SYNOPSIS
update-initramfs {-c|-d|-u} [-k version] [-v] [-b directory] [-s time-
stamp]
update-initramfs --version
update-initramfs -h
DESCRIPTION
The update-initramfs script manages your initramfs images on your local
box. It keeps track of the existing initramfs archives in /boot. There
are three modes of operation create, update or delete. You must at
least specify one of those modes.
The initramfs is a gzipped cpio archive. At boot time, the kernel un-
packs that archive into RAM disk, mounts and uses it as initial root
file system. All finding of the root device happens in this early user-
space.
OPTIONS
-k version
Set the specific kernel version for whom the initramfs will be
generated. For example the output of uname -r for your currently
running kernel. This argument is optional for update. The de-
fault is the latest kernel version.
The use of "all" for the version string specifies that up-
date-initramfs should operate on all installed kernel versions
(with -c), or on all installed kernel versions that already have
an initramfs (with -d or -u).
-c This mode creates a new initramfs.
-u This mode updates an existing initramfs.
-d This mode deletes an existing initramfs.
-v This option increases the amount of information you are given
during the chosen action.
-b directory
Set an different bootdir for the image creation.
-s timestamp
This parameter sets a Unix time stamp (seconds since 1970) for
the update mode. An existing initramfs will only be updated if
it is not newer than the specified Unix time stamp. This parame-
ter will be ignored if set to an empty string.
--version
Print the version information of the underlying initrd generation
tool and exit.
-h, --help
Print a short help page describing the available options in up-
date-initramfs.
EXAMPLES
Update the initramfs of the newest kernel:
update-initramfs -u
Create the initramfs for a specific kernel:
update-initramfs -c -k 2.6.18-1-686
FILES
/etc/initramfs-tools/update-initramfs.conf
AUTHOR
The initramfs-tools are written by Maximilian Attems <maks@debian.org>,
Jeff Bailey <jbailey@raspberryginger.com> and numerous others.
SEE ALSO
initramfs.conf(5), initramfs-tools(7), mkinitramfs(8), lsinitramfs(8).
initramfs-tools 2014/10/16 UPDATE-INITRAMFS(8)
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