Skip to main content

Configuring a Linux image sourced from CoreWeave Cloud

Objective: Use our Packer Virtual Server to configure a Linux image from CoreWeave Cloud.
Overview: Combining examples from Configuring a Windows Image sourced from CoreWeave Cloud and Configuring an externally sourced cloud Linux image, we will use our Packer Worker Virtual Server to configure a Linux image sourced from CoreWeave Cloud.

References:​

Selecting a source image​

Following the example in Copying CoreWeave Images to a Writeable PVC, we will search for the latest CentOS image in the vd-images namespace:

We will then clone this image into our namespace:

Example
apiVersion: cdi.kubevirt.io/v1beta1

kind: DataVolume

metadata:

  annotations:

  labels:

  name: centos7-docker-master-clone-20210813-ord1

  namespace: tenant-<name>

spec:

  pvc:

    accessModes:

    - ReadWriteOnce

    resources:

      requests:

        storage: 40Gi

    storageClassName: block-nvme-ord1

    volumeMode: Block

  source:

    pvc:

      name: centos7-docker-master-20210813-ord1

      namespace: vd-images

Setting up the Packer Environment​

Following the example in Creating a Packer Worker Virtual Server, we'll mount our CentOS PVC as an additional disk:

title="packer_vs.yaml"
    additionalDisks:

    - name: CentOS_7

      spec:

        persistentVolumeClaim:

          claimName: centos7-docker-master-clone-20210813-ord1

Configuring the Packer manifest​

Our Packer manifest will be a combination of our previous Windows and Ubuntu examples:

title="centos.json"
{

    "builders": [

        {

            "type": "qemu",

            "accelerator": "kvm",

            "communicator": "ssh",

            "headless": true,

            "disk_image": false,

            "cpus": "6",

            "memory": "16384",

            "format": "raw",

            "iso_checksum": "none",

            "iso_url": "/dev/vdb",

            "skip_resize_disk": false,

            "skip_compaction": false,

            "disk_size": "40000M",

            "qemuargs": [

                ["-machine","pc-q35-4.2,accel=kvm,usb=off,vmport=off,dump-guest-core=off"],

                ["-cpu", "host"],

                [ "-smp", "cpus=4,sockets=1" ],

                [ "-cdrom", "cidata.iso" ],

                ["-drive", "file=/dev/vdb"]

            ],

            "ssh_username": "user",

            "ssh_password": "packer",

            "net_device": "virtio-net",

            "shutdown_command": "sudo shutdown --poweroff --no-wall now"

        }

    ],

    "provisioners": [

        {

            "type": "shell",

            "execute_command": "{{.Vars}} sudo -S -E bash '{{.Path}}'",

            "inline": [

                "yum update -y",

                "yum upgrade -y",

                "yum clean all -y"

            ]

        }

    ]

}
Note

/dev/vdb refers to our cloned block device

Note

The credentials in this configuration are created when the VM reads the image output of create-ci-data.sh

Note

In this example, we are using the shell provisioner to install package updates. To learn more and view more provisioners, view Hashicorp's documentation.

Execute Packer docker image​

Similar to our Windows example, we'll kick off our CentOS build with launch-docker.sh win.json. Since we're writing to our PVC directly, all changes are made directly to our cloned disk.

Last updated on