linux-update-symlinks

LINUX-UPDATE-SYMLINKS(1)    General Commands Manual   LINUX-UPDATE-SYMLINKS(1)

NAME
       linux-update-symlinks   -  maintain  symlinks  to  default  kernel  and
       initramfs

SYNOPSIS
       linux-update-symlinks {install|upgrade|remove} VERSION IMAGE-PATH

DESCRIPTION
       linux-update-symlinks is intended to be called from  the  postinst  and
       postrm  maintainer  scripts  of  Linux  kernel  packages.  The postinst
       script must pass the first argument install  or  upgrade  depending  on
       whether a fresh installation or an upgrade has taken place.

       The  VERSION argument must be the kernel version string as shown by un-
       ame -r and used in filenames.

       The IMAGE-PATH argument must be the absolute filename of the kernel im-
       age.

       By  default,  this  command  maintains  symlinks in the root directory.
       This behaviour can be modified by settings in /etc/kernel-img.conf:

       image_dest
              Specifies the directory in which to maintain symlinks
       link_in_boot
              If set to a true value, specifies that the directory is /boot
       no_symlinks
              If set to a false value, disables maintenance of symlinks

       The symlinks for the primary default kernel version are  named  vmlinuz
       or  vmlinux  (depending  on whether the architecture normally uses com-
       pressed kernel images) and initrd.img (if it uses an  initramfs).   The
       symlinks  for the secondary default have the same names with the suffix
       .old.

       If symlink maintenance is disabled, linux-update-symlinks does nothing,
       successfully.  Otherwise it makes a list of kernel versions in decreas-
       ing order of priority:

       o The given VERSION, if the first argument is install

       o The current primary default version, if it exists and is not  already
         listed

       o The  current  secondary  default version, if it exists and is not al-
         ready listed

       o All other versions whose files are installed, excluding the specified
         VERSION if the first argument is remove, in decreasing version order

       The  top  two entries on the list are the new primary and secondary de-
       fault versions, and it updates the symlinks accordingly.  In case there
       is  only one entry, this is both the primary and secondary default ver-
       sion.  If there are no entries, there are no default  versions  and  it
       removes the default symlinks.

ENVIRONMENT VARIABLES
       INITRD When the first argument is install or upgrade, linux-update-sym-
              links assumes that the given VERSION will use an  initramfs  un-
              less this variable is set to No.

FILES
       /boot/initrd.img-*
              Installed initramfs images

       /boot/vmlinuz-* | /boot/vmlinux-*
              Installed kernel images
       /etc/kernel-img.conf
              Configuration  file  specifying whether and where to create sym-
              links
       /initrd.img
              Symlink to the initramfs image for the primary default version
       /initrd.img.old
              Symlink to the initramfs image for the secondary default version
       /vmlinuz | /vmlinux
              Symlink to the kernel image for the primary default version
       /vmlinuz.old | /vmlinux.old
              Symlink to the kernel image for the secondary default version

AUTHOR
       linux-update-symlinks and this manual page were written by  Ben  Hutch-
       ings as part of the Debian linux-base package.

SEE ALSO
       kernel-img.conf(5), linux-version(1).

                                  5 June 2016         LINUX-UPDATE-SYMLINKS(1)