Preparing the Overcloud Image

Getting Started with Napatech Link-Virtualization™ Software

Napatech SmartNIC
Content Type
Getting Started
Getting Started Guide
Capture Software Version
Link-Virtualization™ Software 4.5

The provided script installs the RPM packages for the Napatech OVS/DPDK and configures the overcloud image.

About this task

This describes a series of actions to modify the overcloud image.

Before you begin

Do not perform this procedure on the director node. Use another server to build the image for overcloud deployment.


  1. Download the overcloud image.
    Unpack the file.
    tar xf overcloud-full.tar
  2. Install the required packages.
    sudo dnf groupinstall -y "Development Tools" 
    sudo dnf groupinstall -y "Virtualization Host"
    sudo dnf install -y qemu-kvm qemu-img
    sudo dnf install -y libguestfs-tools-c
  3. Update the QEMU access rights.
    vim /etc/libvirt/qemu.conf
    Add the following lines to the file.
    user = "root"
    group = "root"
    Start the libvirt service.
    sudo systemctl enable libvirtd
    sudo systemctl start libvirtd
  4. Set the root password.
    sudo virt-customize -a overcloud-full.qcow2 --root-password password:1234
    An output example:
    [   0.0] Examining the guest ...
    [  12.9] Setting a random seed
    [  12.9] Setting the machine ID in /etc/machine-id
    [  12.9] Setting passwords
    [  16.0] Finishing off
  5. Run a VM with the overcloud image.
    sudo /usr/libexec/qemu-kvm -m 4096 -drive \
    file=overcloud-full.qcow2,if=virtio -net nic,model=virtio -net nic \
    -net user,hostfwd=tcp::10035-:22 -kernel overcloud-full.vmlinuz \
    -append "rw root=/dev/vda console=ttyS0" \
    -initrd overcloud-full.initrd  -nographic
    Log in to the VM.
    CentOS Stream 8
    Kernel 4.18.0-373.el8.x86_64 on an x86_64
    Activate the web console with: systemctl enable --now cockpit.socket
    localhost login: root
  6. Copy the provided package from the host to the VM.
    For example:
    scp root@<host>:/root/tripleo/overcloud_image/Napatech/overcloud_packages.tar.gz .
    scp root@<host>:/root/tripleo/overcloud_image/Napatech/ .
    Run the script which installs required packages and configure the overcloud image.
    Delete the script.
    rm -rf /root/
  7. Restart and log in to the VM.
    shutdown -r now
  8. Clean up the overcloud image after changes are made.
    All the packages must be deleted to make disk memory available, and network data must be cleared to keep the image without any network configuration.
    1. Delete all data in the /etc/resolv.conf file.
      # Generated by NetworkManager
      nameserver # delete this line
      nameserver # delete this line
    2. Flush the IP address of network interfaces. For example:
      ip addr flush <network_interface>
      For example:
      ip addr flush ens3
      ip addr flush ens4
    3. Delete the dnf repository files.
      rm -rf /etc/yum.repos.d/*
  9. Shutdown the VM.