On Tue, Feb 25, 2020 at 1:52 AM Joel Kessler <joel@kessler.family> wrote:
I planed to have it like this:

nvme0n1 259:0 0 238.5G 0 disk
|-nvme0n1p1 259:5 0 10G 0 part /mnt/data
|-nvme0n1p2 259:1 0 384M 0 part /boot
|-nvme0n1p3 259:2 0 127M 0 part /boot/efi
|-nvme0n1p4 259:3 0 1M 0 part
|-nvme0n1p5 259:4 0 225.8G 0 part /sysroot

For a reprovision I would now like to run this on the active fcos

1. docker run -i --rm quay.io/coreos/fcct:v0.2.0 -pretty -strict < /mnt/data/ignition.fcc > /mnt/data/transpiled_config.ign
2. coreos-installer install /dev/nvme0n1 --image-file /mnt/data/fedora_coreos.raw.xz --ignition  /mnt/data/transpiled_config.ign --insecure

Which then should override the currently running os, except for the data partition. 

Step 1 looks fine.  Step 2 won't work; you can't overwrite the root partition while booted from it.  A couple possible alternatives:

- When you want to reprovision, boot from a PXE server on the local network and run coreos-installer from the resulting live system.  Then reboot into the installed system.
- Boot and run from PXE every time, and skip the install to disk altogether.  You can still use the local disk for your data partition.  Note that there are no automatic updates in this mode; updates can only happen by updating the image on the PXE server and rebooting nodes into the new OS version.

--Benjamin Gilbert