This source repository builds packages that work with initramfs-tools
to add function to an initramfs that is likely cloud specific.
Most likely, you do not want to install these packages unless you know
what you're doing.
== growroot ==
This initramfs module will re-write the partition table of a disk
so that the root partition has as much space as possible, bumping it
up to the edge of the disk, or the edge of the next partition.
This is valueable in an environment where a volume can be grown past
its original size. It addresses the following situation:
* The initial [virtual] disk has a partition table on it
* The provisioning system creates a volume with additional space
at the end of the disk (after the root partition)
* the system boots, but cannot use the additional space without a reboot
because the kernel will not re-read the partition table information
of a disk that is in use.
The way this is addressed is:
* in the initramfs unmount the root filesystem
* rewrite the partition table
* tell the kernel to re-read
* remount the root filesystem
== rescuevol ==
When installed the initramfs will check to see if any partitions
with a label of 'RESCUE_VOL' are attached. If such a volume is attached,
it will boot off that volume rather than the root volume.
This is useful in a cloud environment, when the user is able to attach
and detach volumes to a running system, but has no other mechanism
for interupting of fixing a failed boot. It is analogous to inserting
a rescue CD into a system to recover from failure.
It may be helpful in the case where the kernel and ramdisk can be loaded
from the instance, but the system is unusable. This could occur if
an error left ssh access broken or the system didn't come all the way up.
The user could attach a correctly labeled volume, reboot the instance
and access the system to fix it.
If the volume contains a file '/etc/rescuevol-ignore' it will be ignored.
This allows you to fix your instance, create that volume and *not* boot the
rescue volume on next boot