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Prepare ISO image to work with the cloud platform
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Prepare ISO image to work with the cloud platform

If you have uploaded an ISO image with an operating system distribution to the image store, we recommend that you make it fully compatible with the Selectel Cloud Platform. From a compatible image, you can create cloud servers with the same functionality as servers from off-the-shelf images.

For your information

These instructions are for an Oracle Linux image. Other distributions may have different utilities, repositories, and file locations.

  1. Upload the ISO image to the image repository.
  2. Create a cloud server from the downloaded image.
  3. Set up a cloud server.
  4. Create an image from the cloud server boot disk.

1. Download the ISO image to the image store⁠

Use the instructions to Download and create an image.

2. Create a cloud server from the downloaded image⁠

Use the instructions to Create a cloud server.

Select the downloaded image as the source and the network drive as the boot disk.

3. Set up a cloud server⁠

  1. Connect to the cloud server.

  2. Add the OpenStack Selectel repositories to the selectel-openstack.repo file:

    cat <<EOF > /etc/dnf.repos.d/selectel-openstack.repo
    [selectel-openstack]
    name=selectel-openstack
    baseurl=http://mirror.selectel.org/rpm/centos/7/x86_64
    gpgcheck=1
    gpgkey=http://mirror.selectel.org/selectel-openstack.key
    EOF

  3. Update the list of repositories for the package manager:

    dnf update

  4. Install the packages:

    dnf install crontab-randomizer \
    fstrim-blocks qemu-guest-agent \
    set-root-pw \
    cloud-init \
    cloud-utils-growpart \
    compat-openssl10

  5. Navigate to the /etc/cloud/cloud.cfg.d/ directory to create the cloud-init configuration files:

    cd /etc/cloud/cloud.cfg.d/

  6. Prohibit the creation of the ubuntu user:

    cat <<EOF > 10_no_default_users.cfg
    users: []
    EOF

  7. Add data sources for cloud-init-datasources:

    cat <<EOF > 91-dib-cloud-init-datasources.cfg
    datasource_list: [  ConfigDrive, Ec2, None ]
    EOF

  8. Disable the cloud-init and EC2 warning:

    cat <<EOF > 92-ec2-datasource.cfg
    #cloud-config
    datasource:
        Ec2:
            strict_id: false
    EOF

  9. Add download settings:

    cat <<EOF > 99_boot_routines.cfg
    bootcmd:
        - sed -i '/^;/d' /etc/resolv.conf
    EOF

  10. Prevent cloud-init from disabling EC2 metadata:

    cat <<EOF > 99_enable_ec2.cfg
    disable_ec2_metadata: false
    EOF

  11. Add first-boot settings:

    cat <<EOF > 99_first_boot_routines.cfg
    runcmd:
        - sed -i '/NetworkManager/d' /etc/resolv.conf
        - sed -i '/^search/d' /etc/resolv.conf
        - set-root-pw 2> /dev/null
        - crontab-randomizer
    EOF

  12. Prohibit disabling root access via SSH:

    cat <<EOF > 99_keep_root_user.cfg
    disable_root: false
    EOF

  13. Change the timezone:

    cat <<EOF > 99_location.cfg
    locale: en_US.UTF-8
    timezone: UTC
    EOF

  14. Add permission for password authentication via SSH:

    cat <<EOF > 99_ssh_settings.cfg
    ssh_pwauth: true
    no_ssh_fingerprints: true
    ssh_deletekeys: true
    EOF

  15. Configure services autorun to apply changes and work correctly after a server reboot:

    systemctl enable cloud-init
    systemctl enable cloud-init.service
    systemctl enable cloud-config.service
    systemctl enable cloud-final.service
    systemctl enable qemu-guest-agent.service
    systemctl enable cockpit.socket

  16. Perform a hardware reboot of the server.

  17. Reconnect to the cloud server.

    You will see a message that the host ID has changed. This means that cloud-init is successful in booting the operating system:

    @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
    @    WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED!     @
    @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
    IT IS POSSIBLE THAT SOMEONE IS DOING SOMETHING NASTY!
    Someone could be eavesdropping on you right now (man-in-the-middle attack)!
    It is also possible that a host key has just been changed.

4. Create an image from the cloud server boot disk⁠

  1. Create an image from the cloud server boot disk.

  2. Open the OpenStack CLI.

  3. Add properties for the created image:

    openstack image set --property x_sel_image_owner=Selectel <image>
    openstack image set --property hw_qemu_guest_agent=yes <image>

    Specify <image> — image ID or name. The list can be viewed with openstack image list --private

  4. Optional: after creating an image from the disk , remove the cloud server.