Provisioning Fedora CoreOS on IBM Cloud

This guide shows how to provision new Fedora CoreOS (FCOS) instances in IBM Cloud VPC Generation 2 for either the x86_64 or s390x architectures.

Prérequis

Before provisioning an FCOS machine, you must have an Ignition configuration file containing your customizations. If you do not have one, see Producing an Ignition File.

Fedora CoreOS has a default core user that can be used to explore the OS. If you want to use it, finalize its configuration by providing e.g. an SSH key.

If you do not want to use Ignition to get started, you can make use of the Afterburn support.

You also need to have access to an IBM Cloud account. The examples below use the ibmcloud command-line tool, which must be separately installed and configured beforehand. Folow the directions at https://cloud.ibm.com/docs/cli?topic=cli-install-ibmcloud-cli to install the ibmcloud CLI. You’ll need both the cloud-object-storage and infrastructure-service plugins installed. This can be done with:

  • ibmcloud plugin install cloud-object-storage

  • ibmcloud plugin install infrastructure-service

After you’ve logged in using ibmcloud login you can set a target region:

Target a specific region
REGION='us-east' # run `ibmcloud regions` to view options
ibmcloud target -r $REGION
Target a specific resource group
RESOURCE_GROUP='my-resource-group'
ibmcloud resource group-create $RESOURCE_GROUP # Create the resource group if it doesn't exist
ibmcloud target -g $RESOURCE_GROUP

There are also several other pieces that need to be in place, like a VPC, SSH keys, networks, permissions, etc. Unfortunately, this guide is not a comprehensive IBM Cloud guide. If you are new to IBM Cloud please familiarize yourself using the documentation for VPC Gen2 first.

Creating an Image

The following sets of commands will show you how to download the most recent image for a stream, upload it to cloud storage, and then create the cloud image in IBM Cloud. It is worth noting that Fedora CoreOS comes in three streams, with different update schedules per stream. These steps show the stable stream as an example, but can be used for other streams too.

Fetch the latest image suitable for your target stream (or download and verify it from the web).
STREAM='stable'
ARCH='x86_64' # or 's390x'
coreos-installer download -s $STREAM -a $ARCH -p ibmcloud -f qcow2.xz --decompress
Create a Service Account for uploading and an Authorization Policy to allow creating images from the uploaded objects.
BUCKET='my-unique-bucket'
ibmcloud resource service-instance-create "${BUCKET}-service-instance" cloud-object-storage standard global

SERVICE_INSTANCE_ID='25df0db0-89a4-4cb8-900f-ed8b44259f80' # from just created service account
ibmcloud iam authorization-policy-create is --source-resource-type image cloud-object-storage Reader --target-service-instance-id $SERVICE_INSTANCE_ID
Upload the fetched image file to IBM Cloud Object Storage.
FCOS_VERSION='...'
FILE="fedora-coreos-${FCOS_VERSION}-ibmcloud.${ARCH}.qcow2"
ibmcloud cos create-bucket --bucket $BUCKET --ibm-service-instance-id $SERVICE_INSTANCE_ID
ibmcloud cos upload --bucket=$BUCKET --key=$FILE --file=$FILE
Create the image from the storage object.
IMAGE=${FILE:0:-6}     # pull off .qcow2
IMAGE=${IMAGE//[._]/-} # replace . and _ with -
[ $ARCH == 'x86_64' ] && OSNAME='fedora-coreos-stable-amd64'
[ $ARCH == 's390x' ] && OSNAME='red-8-s390x-byol'
ibmcloud is image-create $IMAGE --file "cos://${REGION}/${BUCKET}/${FILE}" --os-name $OSNAME
For s390x we use --os-name=red-8-s390x-byol (a RHEL 8 profile) here because there is not currently a fedora-coreos-stable-s390x profile to use.

You’ll have to wait for the image creation process to finish and go from pending to available before you can use the image. Monitor with the following command:

Monitor image creation progress by viewing the images in your account
ibmcloud is images --visibility private

Launching a VM instance

Now that you have an image created in your account you can launch a VM instance. You’ll have to specify several pieces of information in the command. Embedded in the example below are tips for how to grab that information before launching an instance.

You’ll also need the Ignition config you created earlier. Here it is represented in the example command as @example.ign, which indicates a file in the current directory named example.ign. The @ is required before the path to the ignition file.

Launching a VM instance
NAME='instance1'
ZONE="${REGION}-1" # view more with `ibmcloud is zones`
PROFILE='bx2-2x8' # view more with `ibmcloud is instance-profiles`
VPC='r014-c9c65cc4-cfd3-44de-ad54-865aac182ea1'    # `ibmcloud is vpcs`
IMAGE='r014-1823b4cf-9c63-499e-8a27-b771be714ad8'  # `ibmcloud is images --visibility private`
SUBNET='0777-bf99cbf4-bc82-4c46-895a-5b7304201182' # `ibmcloud is subnets`
SSHKEY='r014-b44c37d0-5c21-4c2b-aba2-438a5b0a228d' # `ibmcloud is keys`
ibmcloud is instance-create $NAME $VPC $ZONE $PROFILE $SUBNET --image $IMAGE --keys $SSHKEY --user-data @example.ign
If needed you may have to first create a subnet with a command like 'ibmcloud is subnet-create my-subnet $VPC --ipv4-address-count 256 --zone $ZONE'.
Make sure you choose an appropriate instance type based on your architecture. For example, you may want to use bz2-2x8 instead of bx2-2x8 above if you are targetting s390x.

Next, if you’d like to SSH into the instance from outside IBM Cloud, you can assign a public IP to the instance:

Create and Assign a Floating IP
ibmcloud is floating-ip-reserve floating-ip-1 --zone=$ZONE
FIP='72251a2e-d6c5-42b4-97b0-b5f8e8d1f479'
NIC='0777-dd174c80-dbd9-41b1-b221-39bbcef8a481' # find from `ibmcloud is instance` output
ibmcloud is floating-ip-update $FIP --nic $NIC

And you now should be able to SSH into the instance using the IP address associated with the floating IP.

Example connecting
ssh core@<ip address>