Customizing LiveISO for BareMetal

[imranrazakhan]

I customized LiveISO with following steps, Looking for suggestion about this process or any improvement recommendations (we can add in documentation)

• Embed ignition in LiveISO

sudo podman run --pull=always --privileged --rm \
    -v /dev:/dev -v /run/udev:/run/udev -v .:/data \
    quay.io/coreos/coreos-installer:release \
    iso embed /data/fedora-coreos-31.20200118.3.0-live.x86_64.iso -c /data/config.ign -f

• Mounted ISO from step1 and copied content in local directory like below

mkdir -p ~/mnt/fcosiso
mount -o loop fedora-coreos-31.20200118.3.0-live.x86_64.iso ~/mnt/fcosiso/
mkdir -p ~/fcos_usb_build/
rsync -av ~/mnt/fcosiso/ ~/fcos_usb_build/
sudo umount ~/mnt/fcosiso

• Changed isolinux.cfg to add static IP support

vi ~/fcos_usb_build/isolinux/isolinux.cfg
append initrd=/images/initramfs.img mitigations=auto,nosmt systemd.unified_cgroup_hierarchy=0 coreos.liveiso=fedora-coreos-31.20200118.3.0 rd.neednet=1 **ip=192.168.127.11::192.168.127.254:255.255.255.0:::off** ignition.firstboot ignition.platform.id=metal

• Create customized ISO

cd ~/fcos_usb_build
mkisofs -o fcos.iso -b isolinux/isolinux.bin -c isolinux/boot.cat -no-emul-boot -V "FCOSISO" -boot-load-size 4 -boot-info-table -R -J -v -T .

I tested resulted ISO and its working.

[bgilbert]

If the only reason you're customizing the ISO is to configure networking using kernel arguments, we could support that directly in coreos-installer iso embed. All it'd need to do is add the kargs to /etc/cmdline.d/coreos-installer.conf within the embedded cpio archive.

[imranrazakhan]

@bgilbert intention is not only to add/override kargs, i am also looking for a way to add custom directory.

As in CentOS if we create custom resources under isolinux directory then these custom resources available at /mnt/install/repo/**custom** during installation.

[bgilbert]

We now have coreos-installer iso customize, which provides several mechanisms for customizing an ISO image. For example, the tool can configure kernel arguments, network settings, and coreos-installer install command-line arguments. It can also inject Ignition configs for the live and/or installed system, if you need to write arbitrary files or systemd units.

[khaaliid]

@bgilbert , I went through the coreos-installer docs and I am not able to find any way to add an repo contains a custom RPMs. Is that doable in the current release ?

[jlebon]

@bgilbert , I went through the coreos-installer docs and I am not able to find any way to add an repo contains a custom RPMs. Is that doable in the current release ?

This is more closely related to #681, which is still in our backlog. Once we have that and working for live systems too, I could imagine an iso/pxe customize sugar which wraps it.

For now, you'll need to do this manually similarly to how it's documented in https://docs.fedoraproject.org/en-US/fedora-coreos/os-extensions/ (but note these steps currently do not work for live systems if that's your target use case).