root partition resizer for initramfs-tools

Helper module for debian/ubuntu's initramfs-tools to allow shrinking the root partition before it gets mounted.

Known Limitations

1. currently only supports ext4
2. root= needs to be in UUID mode

Dependencies

• make
• gdisk
• parted

Usage

Get the sources

git clone https://gitlab.com/mnemoc/initramfs-resizer
cd initramfs-resizer

if you want to use the default settings:

make install
reboot

and if you want to fiddle with the paramters first

make install UPDATE_INITRAMFS=true
vi /etc/default/resizer
update-initramfs -u
reboot

and after the reboot, uninstall it

cd initramfs-resizer
make uninstall

if you used LVM mode it's adviced to reinstall the bootloader

e.g.:

update-grub
grub-install /dev/sda

Parameters

• SPARE represents the amount of free space we want in the root partition. Defaults to 10GiB.
• USE_LVM name of the LVM volume group which the shrunk root partition should be part of. Defaults to no (as in, "do not migrate to LVM").
• EXIT_DELAY integer seconds to wait at the end so you have time to look at the output. Defaults to 10.

LVM Booting

The first time you reboot in USE_LVM mode the bootloader will have used the old regular partition, but the next time you'll need your bootloader to have been reconfigured for lvm support.