Run standard Ubuntu Kernels on Scaleway x86_64 Ubuntu instances

Scaleway is great but I've grown tired of theier old home-brewed kernels with missing modules and features. Why not use standard Ubuntu kernels instead? With this package you can use standard Ubuntu kernels on your Scaleway x86_64 instances by the magic of KEXEC.

Be aware that you don't need all of this if you are using the newer Scaleway locally booted instances (eg. START1). This instances use the distributions kernel anyhow.

Requirements

Just make sure your current Scaleway kernel has KEXEC support. E.g. 4.9.20 std #1 bootscript. You can adjust this via the bootscript setting in the Advanced section of the cloud.scaleway.com interface.

Install

1. Make sure your system is up-to-date and get the Ubuntu package:
   curl -LO https://github.com/stuffo/scaleway-ubuntukernel/releases/download/v1.2/scaleway-ubuntukernel_1.2-1_amd64.deb
2. You can skip this step if you already installed any kernel package providing linux-image. Otherwise, get some Ubuntu kernel. E.g. current mainline kernels from http://kernel.ubuntu.com/~kernel-ppa/mainline:
   curl -LO http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.10.3/linux-image-4.10.3-041003-generic_4.10.3-041003.201703142331_amd64.deb
apt install ./linux-image-4.10.3-041003-generic_4.10.3-041003.201703142331_amd64.deb
   Ignore/dismiss all Grub related setup messages, you don't need it.
3. Install this package:
   apt install ./scaleway-ubuntukernel_1.2-1_amd64.deb
   Say No when asked about using Kexec reboot, it will interfere with this kexec service.
4. Make sure Ubuntu kexec service is disabled. Required as Ubuntu will kexec too early and leave a dirty filesystem. systemctl disable kexec
5. Reboot. That's it. Your system will kexec into your Ubuntu kernel on startup.

Uninstall

Either remove the package or just disable the service: systemctl disable scaleway-ubuntukernel

Troubleshooting

You can run ubuntukernel-load.sh manually as root. It is quite verbose. Be aware that your system will reboot (kexec) if all went fine.

If your initrd or kernel is bad you can get stuck with a non booting system. Add a server tag in the Scaleway webui with the name ubuntukernel_disabled and kexec won't be executed on bootup anymore.

Other usefull Scaleway related tags are INITRD_POST_SHELL=1 which will drop you in a shell after the whole initrd shebang is done so you can tinker with your filesystem. Also consider INITRD_VERBOSE=1 to make initrd more verbose. INITRD_DEBUG=1 is maximum verbose and will trace all commands that get executed in initrd.

Build

Make sure you have devscripts package installed.

1. clone repo git clone https://github.com/stuffo/scaleway-ubuntukernel.git
2. run debuild to build debian package
   debuild -i -us -uc -b

TODO

• account scaleway initrd version for automatic initrd regeneration on change