Add support for Kata Containers (#6256)

* Install Kata Containers as additional container runtime

* Create RuntimeClasses for Kata Containers

* Updated Vagrant to optionally run without Docker as container manager

* Updated Vagrant to optionally use Libvirt nested virtualization

* Add Kata Containers documentation

* Fix lint errors

* Add kata_containers_enabled to kubespray-defaults

* Fixed typo error

* Fixed typo error

Vagrantfile

@@ -55,6 +55,8 @@ $os ||= "ubuntu1804"
 $network_plugin ||= "flannel"
 # Setting multi_networking to true will install Multus: https://github.com/intel/multus-cni
 $multi_networking ||= false
+$download_run_once ||= "True"
+$download_force_cache ||= "True"
 # The first three nodes are etcd servers
 $etcd_instances ||= $num_instances
 # The first two nodes are kube masters
@@ -69,6 +71,7 @@ $override_disk_size ||= false
 $disk_size ||= "20GB"
 $local_path_provisioner_enabled ||= false
 $local_path_provisioner_claim_root ||= "/opt/local-path-provisioner/"
+$libvirt_nested ||= false
 
 $playbook ||= "cluster.yml"
 
@@ -146,6 +149,8 @@ Vagrant.configure("2") do |config|
       end
 
       node.vm.provider :libvirt do |lv|
+        lv.nested = $libvirt_nested
+        lv.cpu_mode = "host-model"
         lv.memory = $vm_memory
         lv.cpus = $vm_cpus
         lv.default_prefix = 'kubespray'
@@ -196,11 +201,11 @@ Vagrant.configure("2") do |config|
         "flannel_interface": "eth1",
         "kube_network_plugin": $network_plugin,
         "kube_network_plugin_multus": $multi_networking,
-        "download_run_once": "True",
+        "download_run_once": $download_run_once,
         "download_localhost": "False",
         "download_cache_dir": ENV['HOME'] + "/kubespray_cache",
         # Make kubespray cache even when download_run_once is false
-        "download_force_cache": "True",
+        "download_force_cache": $download_force_cache,
         # Keeping the cache on the nodes can improve provisioning speed while debugging kubespray
         "download_keep_remote_cache": "False",
         "docker_rpm_keepcache": "1",

docs/kata-containers.md

+# Kata Containers
+
+[Kata Containers](https://katacontainers.io) is a secure container runtime with lightweight virtual machines that supports multiple hypervisor solutions.
+
+## Hypervisors
+
+_Qemu_ is the only hypervisor supported by Kubespray.
+
+## Installation
+
+To use Kata Containers, set the following variables:
+
+**k8s-cluster.yml**:
+
+```yaml
+container_manager: containerd
+kata_containers_enabled: true
+```
+
+**etcd.yml**:
+
+```yaml
+etcd_deployment_type: host
+```
+
+## Configuration
+
+### Recommended : Pod Overhead
+
+[Pod Overhead](https://kubernetes.io/docs/concepts/configuration/pod-overhead/) is a feature for accounting for the resources consumed by the Runtime Class used by the Pod.
+
+When this feature is enabled, Kubernetes will count the fixed amount of CPU and memory set in the configuration as used by the virtual machine and not by the containers running in the Pod.
+
+Pod Overhead is mandatory if you run Pods with Kata Containers that use [resources limits](https://kubernetes.io/docs/concepts/configuration/manage-resources-containers/#requests-and-limits).
+
+**Set cgroup driver**:
+
+To enable Pod Overhead feature you have to configure Kubelet with the appropiate cgroup driver, using the following configuration:
+
+```yaml
+kubelet_cgroup_driver: cgroupfs
+```
+
+**Qemu hypervisor configuration**:
+
+The configuration for the Qemu hypervisor uses the following values:
+
+```yaml
+kata_containers_qemu_overhead: true
+kata_containers_qemu_overhead_fixed_cpu: 10m
+kata_containers_qemu_overhead_fixed_memory: 290Mi
+```
+
+### Optional : Select Kata Containers version
+
+Optionally you can select the Kata Containers release version to be installed. The available releases are published in [GitHub](https://github.com/kata-containers/runtime/releases).
+
+```yaml
+kata_containers_version: 1.11.1
+```
+
+### Optional : Debug
+
+Debug is disabled by default for all the components of Kata Containers. You can change this behaviour with the following configuration:
+
+```yaml
+kata_containers_qemu_debug: 'false'
+```

inventory/sample/group_vars/k8s-cluster/k8s-cluster.yml

@@ -171,6 +171,9 @@ dns_domain: "{{ cluster_name }}"
 ## docker for docker, crio for cri-o and containerd for containerd.
 container_manager: docker
 
+# Additional container runtimes
+kata_containers_enabled: false
+
 ## Settings for containerd runtimes (only used when container_manager is set to containerd)
 #
 # Settings for default containerd runtime

roles/container-engine/containerd/templates/config.toml.j2

@@ -38,6 +38,13 @@ disabled_plugins = ["restart"]
   runtime_engine = "{{ containerd_default_runtime.engine }}"
   runtime_root = "{{ containerd_default_runtime.root }}"
 
+{% if kata_containers_enabled %}
+[plugins.cri.containerd.runtimes.kata-qemu]
+  runtime_type = "io.containerd.kata-qemu.v2"
+  [plugins.cri.containerd.runtimes.kata-qemu.options]
+    ConfigPath = "/etc/kata-containers/configuration-qemu.toml"
+{% endif %}
+
 {% for runtime in containerd_runtimes %}
 [plugins.cri.containerd.runtimes.{{ runtime.name }}]
   runtime_type = "{{ runtime.type }}"

roles/container-engine/kata-containers/defaults/main.yml

+---
+
+kata_containers_version: 1.11.1
+kata_containers_release_url: https://github.com/kata-containers/runtime/releases/download/{{ kata_containers_version }}/kata-static-{{ kata_containers_version }}-{{ ansible_architecture }}.tar.xz
+kata_containers_dir: /opt/kata
+kata_containers_config_dir: /etc/kata-containers
+kata_containers_containerd_bin_dir: /usr/local/bin
+
+kata_containers_qemu_default_memory: "{{ ansible_memtotal_mb }}"
+kata_containers_qemu_debug: 'false'
+kata_containers_qemu_sandbox_cgroup_only: 'true'
+kata_containers_qemu_enable_mem_prealloc: 'false'

roles/container-engine/kata-containers/tasks/main.yml

+---
+
+- name: Download artifacts
+  unarchive:
+    src: "{{ kata_containers_release_url }}"
+    dest: /
+    remote_src: true
+
+- name: Create config directory
+  file:
+    path: "{{ kata_containers_config_dir }}"
+    state: directory
+
+- name: Set configuration
+  template:
+    src: "{{ item }}.j2"
+    dest: "{{ kata_containers_config_dir }}/{{ item }}"
+  with_items:
+    - configuration-qemu.toml
+
+- name: Set containerd bin
+  vars:
+    shim: "{{ item }}"
+  template:
+    dest: "{{ kata_containers_containerd_bin_dir }}/containerd-shim-kata-{{ item }}-v2"
+    src: containerd-shim-kata-v2.j2
+    mode: 0755
+  with_items:
+    - qemu

roles/container-engine/kata-containers/templates/configuration-qemu.toml.j2

+# Copyright (c) 2017-2019 Intel Corporation
+#
+# SPDX-License-Identifier: Apache-2.0
+#
+
+# XXX: WARNING: this file is auto-generated.
+# XXX:
+# XXX: Source file: "cli/config/configuration-qemu.toml.in"
+# XXX: Project:
+# XXX:   Name: Kata Containers
+# XXX:   Type: kata
+
+[hypervisor.qemu]
+path = "/opt/kata/bin/qemu-system-x86_64"
+kernel = "/opt/kata/share/kata-containers/vmlinuz.container"
+image = "/opt/kata/share/kata-containers/kata-containers.img"
+machine_type = "pc"
+
+# Optional space-separated list of options to pass to the guest kernel.
+# For example, use `kernel_params = "vsyscall=emulate"` if you are having
+# trouble running pre-2.15 glibc.
+#
+# WARNING: - any parameter specified here will take priority over the default
+# parameter value of the same name used to start the virtual machine.
+# Do not set values here unless you understand the impact of doing so as you
+# may stop the virtual machine from booting.
+# To see the list of default parameters, enable hypervisor debug, create a
+# container and look for 'default-kernel-parameters' log entries.
+kernel_params = ""
+
+# Path to the firmware.
+# If you want that qemu uses the default firmware leave this option empty
+firmware = ""
+
+# Machine accelerators
+# comma-separated list of machine accelerators to pass to the hypervisor.
+# For example, `machine_accelerators = "nosmm,nosmbus,nosata,nopit,static-prt,nofw"`
+machine_accelerators=""
+
+# Default number of vCPUs per SB/VM:
+# unspecified or 0                --> will be set to 1
+# < 0                             --> will be set to the actual number of physical cores
+# > 0 <= number of physical cores --> will be set to the specified number
+# > number of physical cores      --> will be set to the actual number of physical cores
+default_vcpus = 1
+
+# Default maximum number of vCPUs per SB/VM:
+# unspecified or == 0             --> will be set to the actual number of physical cores or to the maximum number
+#                                     of vCPUs supported by KVM if that number is exceeded
+# > 0 <= number of physical cores --> will be set to the specified number
+# > number of physical cores      --> will be set to the actual number of physical cores or to the maximum number
+#                                     of vCPUs supported by KVM if that number is exceeded
+# WARNING: Depending of the architecture, the maximum number of vCPUs supported by KVM is used when
+# the actual number of physical cores is greater than it.
+# WARNING: Be aware that this value impacts the virtual machine's memory footprint and CPU
+# the hotplug functionality. For example, `default_maxvcpus = 240` specifies that until 240 vCPUs
+# can be added to a SB/VM, but the memory footprint will be big. Another example, with
+# `default_maxvcpus = 8` the memory footprint will be small, but 8 will be the maximum number of
+# vCPUs supported by the SB/VM. In general, we recommend that you do not edit this variable,
+# unless you know what are you doing.
+default_maxvcpus = 0
+
+# Bridges can be used to hot plug devices.
+# Limitations:
+# * Currently only pci bridges are supported
+# * Until 30 devices per bridge can be hot plugged.
+# * Until 5 PCI bridges can be cold plugged per VM.
+#   This limitation could be a bug in qemu or in the kernel
+# Default number of bridges per SB/VM:
+# unspecified or 0   --> will be set to 1
+# > 1 <= 5           --> will be set to the specified number
+# > 5                --> will be set to 5
+default_bridges = 1
+
+# Default memory size in MiB for SB/VM.
+# If unspecified then it will be set 2048 MiB.
+default_memory = {{ kata_containers_qemu_default_memory }}
+#
+# Default memory slots per SB/VM.
+# If unspecified then it will be set 10.
+# This is will determine the times that memory will be hotadded to sandbox/VM.
+#memory_slots = 10
+
+# The size in MiB will be plused to max memory of hypervisor.
+# It is the memory address space for the NVDIMM devie.
+# If set block storage driver (block_device_driver) to "nvdimm",
+# should set memory_offset to the size of block device.
+# Default 0
+#memory_offset = 0
+
+# Specifies virtio-mem will be enabled or not.
+# Please note that this option should be used with the command
+# "echo 1 > /proc/sys/vm/overcommit_memory".
+# Default false
+#enable_virtio_mem = true
+
+# Disable block device from being used for a container's rootfs.
+# In case of a storage driver like devicemapper where a container's 
+# root file system is backed by a block device, the block device is passed
+# directly to the hypervisor for performance reasons. 
+# This flag prevents the block device from being passed to the hypervisor, 
+# 9pfs is used instead to pass the rootfs.
+disable_block_device_use = false
+
+# Shared file system type:
+#   - virtio-9p (default)
+#   - virtio-fs
+shared_fs = "virtio-9p"
+
+# Path to vhost-user-fs daemon.
+virtio_fs_daemon = "/opt/kata/bin/virtiofsd"
+
+# Default size of DAX cache in MiB
+virtio_fs_cache_size = 1024
+
+# Extra args for virtiofsd daemon
+#
+# Format example:
+#   ["-o", "arg1=xxx,arg2", "-o", "hello world", "--arg3=yyy"]
+#
+# see `virtiofsd -h` for possible options.
+virtio_fs_extra_args = []
+
+# Cache mode:
+#
+#  - none
+#    Metadata, data, and pathname lookup are not cached in guest. They are
+#    always fetched from host and any changes are immediately pushed to host.
+#
+#  - auto
+#    Metadata and pathname lookup cache expires after a configured amount of
+#    time (default is 1 second). Data is cached while the file is open (close
+#    to open consistency).
+#
+#  - always
+#    Metadata, data, and pathname lookup are cached in guest and never expire.
+virtio_fs_cache = "always"
+
+# Block storage driver to be used for the hypervisor in case the container
+# rootfs is backed by a block device. This is virtio-scsi, virtio-blk
+# or nvdimm.
+block_device_driver = "virtio-scsi"
+
+# Specifies cache-related options will be set to block devices or not.
+# Default false
+#block_device_cache_set = true
+
+# Specifies cache-related options for block devices.
+# Denotes whether use of O_DIRECT (bypass the host page cache) is enabled.
+# Default false
+#block_device_cache_direct = true
+
+# Specifies cache-related options for block devices.
+# Denotes whether flush requests for the device are ignored.
+# Default false
+#block_device_cache_noflush = true
+
+# Enable iothreads (data-plane) to be used. This causes IO to be
+# handled in a separate IO thread. This is currently only implemented
+# for SCSI.
+#
+enable_iothreads = false
+
+# Enable pre allocation of VM RAM, default false
+# Enabling this will result in lower container density
+# as all of the memory will be allocated and locked
+# This is useful when you want to reserve all the memory
+# upfront or in the cases where you want memory latencies
+# to be very predictable
+# Default false
+enable_mem_prealloc = {{ kata_containers_qemu_enable_mem_prealloc }}
+
+# Enable huge pages for VM RAM, default false
+# Enabling this will result in the VM memory
+# being allocated using huge pages.
+# This is useful when you want to use vhost-user network
+# stacks within the container. This will automatically 
+# result in memory pre allocation
+#enable_hugepages = true
+
+# Enable vhost-user storage device, default false
+# Enabling this will result in some Linux reserved block type
+# major range 240-254 being chosen to represent vhost-user devices.
+enable_vhost_user_store = false
+
+# The base directory specifically used for vhost-user devices.
+# Its sub-path "block" is used for block devices; "block/sockets" is
+# where we expect vhost-user sockets to live; "block/devices" is where
+# simulated block device nodes for vhost-user devices to live.
+vhost_user_store_path = "/var/run/kata-containers/vhost-user"
+
+# Enable file based guest memory support. The default is an empty string which
+# will disable this feature. In the case of virtio-fs, this is enabled
+# automatically and '/dev/shm' is used as the backing folder.
+# This option will be ignored if VM templating is enabled.
+#file_mem_backend = ""
+
+# Enable swap of vm memory. Default false.
+# The behaviour is undefined if mem_prealloc is also set to true
+#enable_swap = true
+
+# This option changes the default hypervisor and kernel parameters
+# to enable debug output where available. This extra output is added
+# to the proxy logs, but only when proxy debug is also enabled.
+# 
+# Default false
+enable_debug = {{ kata_containers_qemu_debug }}
+
+# Disable the customizations done in the runtime when it detects
+# that it is running on top a VMM. This will result in the runtime
+# behaving as it would when running on bare metal.
+# 
+#disable_nesting_checks = true
+
+# This is the msize used for 9p shares. It is the number of bytes 
+# used for 9p packet payload.
+#msize_9p = 8192
+
+# If true and vsocks are supported, use vsocks to communicate directly
+# with the agent and no proxy is started, otherwise use unix
+# sockets and start a proxy to communicate with the agent.
+# Default false
+#use_vsock = true
+
+# If false and nvdimm is supported, use nvdimm device to plug guest image.
+# Otherwise virtio-block device is used.
+# Default is false
+#disable_image_nvdimm = true
+
+# VFIO devices are hotplugged on a bridge by default. 
+# Enable hotplugging on root bus. This may be required for devices with
+# a large PCI bar, as this is a current limitation with hotplugging on 
+# a bridge. This value is valid for "pc" machine type.
+# Default false
+#hotplug_vfio_on_root_bus = true
+
+# Before hot plugging a PCIe device, you need to add a pcie_root_port device.
+# Use this parameter when using some large PCI bar devices, such as Nvidia GPU
+# The value means the number of pcie_root_port
+# This value is valid when hotplug_vfio_on_root_bus is true and machine_type is "q35"
+# Default 0
+#pcie_root_port = 2
+
+# If vhost-net backend for virtio-net is not desired, set to true. Default is false, which trades off
+# security (vhost-net runs ring0) for network I/O performance. 
+#disable_vhost_net = true
+
+#
+# Default entropy source.
+# The path to a host source of entropy (including a real hardware RNG)
+# /dev/urandom and /dev/random are two main options.
+# Be aware that /dev/random is a blocking source of entropy.  If the host
+# runs out of entropy, the VMs boot time will increase leading to get startup
+# timeouts.
+# The source of entropy /dev/urandom is non-blocking and provides a
+# generally acceptable source of entropy. It should work well for pretty much
+# all practical purposes.
+#entropy_source= "/dev/urandom"
+
+# Path to OCI hook binaries in the *guest rootfs*.
+# This does not affect host-side hooks which must instead be added to
+# the OCI spec passed to the runtime.
+#
+# You can create a rootfs with hooks by customizing the osbuilder scripts:
+# https://github.com/kata-containers/osbuilder
+#
+# Hooks must be stored in a subdirectory of guest_hook_path according to their
+# hook type, i.e. "guest_hook_path/{prestart,postart,poststop}".
+# The agent will scan these directories for executable files and add them, in
+# lexicographical order, to the lifecycle of the guest container.
+# Hooks are executed in the runtime namespace of the guest. See the official documentation:
+# https://github.com/opencontainers/runtime-spec/blob/v1.0.1/config.md#posix-platform-hooks
+# Warnings will be logged if any error is encountered will scanning for hooks,
+# but it will not abort container execution.
+#guest_hook_path = "/usr/share/oci/hooks"
+
+[factory]
+# VM templating support. Once enabled, new VMs are created from template
+# using vm cloning. They will share the same initial kernel, initramfs and
+# agent memory by mapping it readonly. It helps speeding up new container
+# creation and saves a lot of memory if there are many kata containers running
+# on the same host.
+#
+# When disabled, new VMs are created from scratch.
+#
+# Note: Requires "initrd=" to be set ("image=" is not supported).
+#
+# Default false
+#enable_template = true
+
+# Specifies the path of template.
+#
+# Default "/run/vc/vm/template"
+#template_path = "/run/vc/vm/template"
+
+# The number of caches of VMCache:
+# unspecified or == 0   --> VMCache is disabled
+# > 0                   --> will be set to the specified number
+#
+# VMCache is a function that creates VMs as caches before using it.
+# It helps speed up new container creation.
+# The function consists of a server and some clients communicating
+# through Unix socket.  The protocol is gRPC in protocols/cache/cache.proto.
+# The VMCache server will create some VMs and cache them by factory cache.
+# It will convert the VM to gRPC format and transport it when gets
+# requestion from clients.
+# Factory grpccache is the VMCache client.  It will request gRPC format
+# VM and convert it back to a VM.  If VMCache function is enabled,
+# kata-runtime will request VM from factory grpccache when it creates
+# a new sandbox.
+#
+# Default 0
+#vm_cache_number = 0
+
+# Specify the address of the Unix socket that is used by VMCache.
+#
+# Default /var/run/kata-containers/cache.sock
+#vm_cache_endpoint = "/var/run/kata-containers/cache.sock"
+
+[proxy.kata]
+path = "/opt/kata/libexec/kata-containers/kata-proxy"
+
+# If enabled, proxy messages will be sent to the system log
+# (default: disabled)
+enable_debug = {{ kata_containers_qemu_debug }}
+
+[shim.kata]
+path = "/opt/kata/libexec/kata-containers/kata-shim"
+
+# If enabled, shim messages will be sent to the system log
+# (default: disabled)
+enable_debug = {{ kata_containers_qemu_debug }}
+
+# If enabled, the shim will create opentracing.io traces and spans.
+# (See https://www.jaegertracing.io/docs/getting-started).
+#
+# Note: By default, the shim runs in a separate network namespace. Therefore,
+# to allow it to send trace details to the Jaeger agent running on the host,
+# it is necessary to set 'disable_new_netns=true' so that it runs in the host
+# network namespace.
+#
+# (default: disabled)
+#enable_tracing = true
+
+[agent.kata]
+# If enabled, make the agent display debug-level messages.
+# (default: disabled)
+enable_debug = {{ kata_containers_qemu_debug }}
+
+# Enable agent tracing.
+#
+# If enabled, the default trace mode is "dynamic" and the
+# default trace type is "isolated". The trace mode and type are set
+# explicity with the `trace_type=` and `trace_mode=` options.
+#
+# Notes:
+#
+# - Tracing is ONLY enabled when `enable_tracing` is set: explicitly
+#   setting `trace_mode=` and/or `trace_type=` without setting `enable_tracing`
+#   will NOT activate agent tracing.
+#
+# - See https://github.com/kata-containers/agent/blob/master/TRACING.md for
+#   full details.
+#
+# (default: disabled)
+#enable_tracing = true
+#
+#trace_mode = "dynamic"
+#trace_type = "isolated"
+
+# Comma separated list of kernel modules and their parameters.
+# These modules will be loaded in the guest kernel using modprobe(8).
+# The following example can be used to load two kernel modules with parameters
+#  - kernel_modules=["e1000e InterruptThrottleRate=3000,3000,3000 EEE=1", "i915 enable_ppgtt=0"]
+# The first word is considered as the module name and the rest as its parameters.
+# Container will not be started when:
+#  * A kernel module is specified and the modprobe command is not installed in the guest
+#    or it fails loading the module.
+#  * The module is not available in the guest or it doesn't met the guest kernel
+#    requirements, like architecture and version.
+#
+kernel_modules=[]
+
+
+[netmon]
+# If enabled, the network monitoring process gets started when the
+# sandbox is created. This allows for the detection of some additional
+# network being added to the existing network namespace, after the
+# sandbox has been created.
+# (default: disabled)
+#enable_netmon = true
+
+# Specify the path to the netmon binary.
+path = "/opt/kata/libexec/kata-containers/kata-netmon"
+
+# If enabled, netmon messages will be sent to the system log
+# (default: disabled)
+enable_debug = {{ kata_containers_qemu_debug }}
+
+[runtime]
+# If enabled, the runtime will log additional debug messages to the
+# system log
+# (default: disabled)
+enable_debug = {{ kata_containers_qemu_debug }}
+#
+# Internetworking model
+# Determines how the VM should be connected to the
+# the container network interface
+# Options:
+#
+#   - macvtap
+#     Used when the Container network interface can be bridged using
+#     macvtap.
+#
+#   - none
+#     Used when customize network. Only creates a tap device. No veth pair.
+#
+#   - tcfilter
+#     Uses tc filter rules to redirect traffic from the network interface
+#     provided by plugin to a tap interface connected to the VM.
+#
+internetworking_model="tcfilter"
+
+# disable guest seccomp
+# Determines whether container seccomp profiles are passed to the virtual
+# machine and applied by the kata agent. If set to true, seccomp is not applied
+# within the guest
+# (default: true)
+disable_guest_seccomp=true
+
+# If enabled, the runtime will create opentracing.io traces and spans.
+# (See https://www.jaegertracing.io/docs/getting-started).
+# (default: disabled)
+#enable_tracing = true
+
+# If enabled, the runtime will not create a network namespace for shim and hypervisor processes.
+# This option may have some potential impacts to your host. It should only be used when you know what you're doing.
+# `disable_new_netns` conflicts with `enable_netmon`
+# `disable_new_netns` conflicts with `internetworking_model=tcfilter` and `internetworking_model=macvtap`. It works only
+# with `internetworking_model=none`. The tap device will be in the host network namespace and can connect to a bridge
+# (like OVS) directly.
+# If you are using docker, `disable_new_netns` only works with `docker run --net=none`
+# (default: false)
+#disable_new_netns = true
+
+# if enabled, the runtime will add all the kata processes inside one dedicated cgroup.
+# The container cgroups in the host are not created, just one single cgroup per sandbox.
+# The runtime caller is free to restrict or collect cgroup stats of the overall Kata sandbox.
+# The sandbox cgroup path is the parent cgroup of a container with the PodSandbox annotation.
+# The sandbox cgroup is constrained if there is no container type annotation.
+# See: https://godoc.org/github.com/kata-containers/runtime/virtcontainers#ContainerType
+sandbox_cgroup_only={{ kata_containers_qemu_sandbox_cgroup_only }}
+
+# Enabled experimental feature list, format: ["a", "b"].
+# Experimental features are features not stable enough for production,
+# they may break compatibility, and are prepared for a big version bump.
+# Supported experimental features:
+# (default: [])
+experimental=[]

roles/container-engine/kata-containers/templates/containerd-shim-kata-v2.j2

+#!/bin/bash
+KATA_CONF_FILE={{ kata_containers_config_dir }}/configuration-{{ shim }}.toml {{ kata_containers_dir }}/bin/containerd-shim-kata-v2 $@

roles/container-engine/meta/main.yml

 ---
 dependencies:
+  - role: container-engine/kata-containers
+    when:
+      - kata_containers_enabled
+    tags:
+      - container-engine
+      - kata-containers
+
   - role: container-engine/cri-o
     when:
       - container_manager == 'crio'

roles/kubernetes-apps/container_runtimes/kata_containers/defaults/main.yaml

+---
+
+kata_containers_qemu_overhead: true
+kata_containers_qemu_overhead_fixed_cpu: 10m
+kata_containers_qemu_overhead_fixed_memory: 290Mi

roles/kubernetes-apps/container_runtimes/kata_containers/tasks/main.yaml

+---
+
+- name: Kata Containers | Create addon dir
+  file:
+    path: "{{ kube_config_dir }}/addons/kata_containers"
+    owner: root
+    group: root
+    mode: 0755
+    recurse: true
+
+- name: Kata Containers | Templates list
+  set_fact:
+    kata_containers_templates:
+      - { name: runtimeclass-kata-qemu, file: runtimeclass-kata-qemu.yml, type: runtimeclass }
+
+- name: Kata Containers | Create manifests
+  template:
+    src: "{{ item.file }}.j2"
+    dest: "{{ kube_config_dir }}/addons/kata_containers/{{ item.file }}"
+  with_items: "{{ kata_containers_templates }}"
+  register: kata_containers_manifests
+  when:
+    - inventory_hostname == groups['kube-master'][0]
+
+- name: Kata Containers | Apply manifests
+  kube:
+    name: "{{ item.item.name }}"
+    kubectl: "{{ bin_dir }}/kubectl"
+    resource: "{{ item.item.type }}"
+    filename: "{{ kube_config_dir }}/addons/kata_containers/{{ item.item.file }}"
+    state: "latest"
+  with_items: "{{ kata_containers_manifests.results }}"
+  when:
+    - inventory_hostname == groups['kube-master'][0]

roles/kubernetes-apps/container_runtimes/kata_containers/templates/runtimeclass-kata-qemu.yml.j2

+---
+kind: RuntimeClass
+apiVersion: node.k8s.io/v1beta1
+metadata:
+  name: kata-qemu
+handler: kata-qemu
+{% if kata_containers_qemu_overhead %}
+overhead:
+  podFixed:
+    cpu: {{ kata_containers_qemu_overhead_fixed_cpu }}
+    memory: {{ kata_containers_qemu_overhead_fixed_memory }}
+{% endif %}

roles/kubernetes-apps/container_runtimes/meta/main.yml

+---
+dependencies:
+  - role: kubernetes-apps/container_runtimes/kata_containers
+    when: kata_containers_enabled
+    tags:
+      - apps
+      - kata-containers
+      - container-runtimes

roles/kubernetes-apps/meta/main.yml

@@ -77,6 +77,13 @@ dependencies:
       - apps
       - persistent_volumes
 
+  - role: kubernetes-apps/container_runtimes
+    when:
+      - inventory_hostname == groups['kube-master'][0]
+    tags:
+      - apps
+      - container-runtimes
+
   - role: kubernetes-apps/container_engine_accelerator
     when: nvidia_accelerator_enabled
     tags:

roles/kubespray-defaults/defaults/main.yaml

@@ -207,6 +207,10 @@ kube_profiling: false
 # Container for runtime
 container_manager: docker
 
+# Enable Kata Containers as additional container runtime
+# When enabled, it requires container_manager=containerd
+kata_containers_enabled: false
+
 # Container on localhost (download images when download_localhost is true)
 container_manager_on_localhost: "{{ container_manager }}"