In order to properly support the IPv6 requirement in OCP 4.4, RHCOS needs to be able to perform DHCPv4 and DHCPv6 in the initramfs to bootstrap the nodes. Part of this is achieved via a newer build of `dracut` from BZ#1787620, however we need to change the default kernel command line in RHCOS artifacts to use `ip=dhcp,dhcp6` as well. This will likely require a change to `coreos-assembler`, for example: https://github.com/coreos/coreos-assembler/blob/master/src/create_disk.sh#L366 And possibly `ignition-dracut`, for example: https://github.com/coreos/ignition-dracut/blob/spec2x/grub/02_ignition_firstboot#L13
This might be achieved with a change to the `image.yaml` file that is consumed by `coreos-assembler` for RHCOS and a patch to `ignition-dracut`
The RHCOS image (44.81.202001241431.0) currently pinned to the installer has the modifed kernel cmdline. Moving to MODIFIED
Latest 4.4 nightly: $ oc image info --output json $(oc adm release info -a ~/openshift-cluster-installs/all-the-pull-secrets.json --image-for=machine-os-content registry.svc.ci.openshift.org/ocp/release:4.4.0-0.nightly-2020-02-13-124128) | jq .config.config.Labels.version "44.81.202002131031-0" Booted QEMU image with `coreos-assembler run -d`, interrupted the boot to inspect boot menu: $ coreos-assembler run -d rhcos-44.81.202002131031-0-qemu.x86_64.qcow2 load_video set gfxpayload=keep insmod gzio linux ($root)/ostree/rhcos-b3173727610b9b7a6404336ae7d850e0a1e22537ac141bf42ce\ 81abac998c3a5/vmlinuz-4.18.0-147.5.1.el8_1.x86_64 rhcos.root=crypt_rootfs cons\ ole=tty0 console=ttyS0,115200n8 ignition.platform.id=qemu rd.luks.options=disc\ ard ignition.firstboot rd.neednet=1 ip=dhcp,dhcp6 ostree=/ostree/boot.1/rhcos/\ b3173727610b9b7a6404336ae7d850e0a1e22537ac141bf42ce81abac998c3a5/0 initrd ($root)/ostree/rhcos-b3173727610b9b7a6404336ae7d850e0a1e22537ac141bf42c\ e81abac998c3a5/initramfs-4.18.0-147.5.1.el8_1.x86_64.img Marking VERIFIED with 44.81.202002131031-0
Since the problem described in this bug report should be resolved in a recent advisory, it has been closed with a resolution of ERRATA. For information on the advisory, and where to find the updated files, follow the link below. If the solution does not work for you, open a new bug report. https://access.redhat.com/errata/RHBA-2020:0581