mirror of
https://github.com/aljazceru/kata-containers.git
synced 2025-12-18 06:44:23 +01:00
0a19340a93
Although the documentation removed is correct, it's not relevant to the current supported versions of CRI-O. Related: #2498 Signed-off-by: Fabiano Fidêncio <fabiano.fidencio@intel.com>
137 lines
5.0 KiB
Markdown
137 lines
5.0 KiB
Markdown
# Run Kata Containers with Kubernetes
|
|
|
|
## Prerequisites
|
|
This guide requires Kata Containers available on your system, install-able by following [this guide](../install/README.md).
|
|
|
|
## Install a CRI implementation
|
|
|
|
Kubernetes CRI (Container Runtime Interface) implementations allow using any
|
|
OCI-compatible runtime with Kubernetes, such as the Kata Containers runtime.
|
|
|
|
Kata Containers support both the [CRI-O](https://github.com/kubernetes-incubator/cri-o) and
|
|
[containerd](https://github.com/containerd/containerd) CRI implementations.
|
|
|
|
After choosing one CRI implementation, you must make the appropriate configuration
|
|
to ensure it integrates with Kata Containers.
|
|
|
|
Kata Containers 1.5 introduced the `shimv2` for containerd 1.2.0, reducing the components
|
|
required to spawn pods and containers, and this is the preferred way to run Kata Containers with Kubernetes ([as documented here](../how-to/how-to-use-k8s-with-cri-containerd-and-kata.md#configure-containerd-to-use-kata-containers)).
|
|
|
|
An equivalent shim implementation for CRI-O is planned.
|
|
|
|
### CRI-O
|
|
For CRI-O installation instructions, refer to the [CRI-O Tutorial](https://github.com/kubernetes-incubator/cri-o/blob/master/tutorial.md) page.
|
|
|
|
The following sections show how to set up the CRI-O configuration file (default path: `/etc/crio/crio.conf`) for Kata.
|
|
|
|
Unless otherwise stated, all the following settings are specific to the `crio.runtime` table:
|
|
```toml
|
|
# The "crio.runtime" table contains settings pertaining to the OCI
|
|
# runtime used and options for how to set up and manage the OCI runtime.
|
|
[crio.runtime]
|
|
```
|
|
A comprehensive documentation of the configuration file can be found [here](https://github.com/cri-o/cri-o/blob/master/docs/crio.conf.5.md).
|
|
|
|
> **Note**: After any change to this file, the CRI-O daemon have to be restarted with:
|
|
>````
|
|
>$ sudo systemctl restart crio
|
|
>````
|
|
|
|
#### Kubernetes Runtime Class (CRI-O v1.12+)
|
|
The [Kubernetes Runtime Class](https://kubernetes.io/docs/concepts/containers/runtime-class/)
|
|
is the preferred way of specifying the container runtime configuration to run a Pod's containers.
|
|
To use this feature, Kata must added as a runtime handler with:
|
|
|
|
```toml
|
|
[crio.runtime.runtimes.kata-runtime]
|
|
runtime_path = "/usr/bin/kata-runtime"
|
|
runtime_type = "oci"
|
|
```
|
|
|
|
You can also add multiple entries to specify alternatives hypervisors, e.g.:
|
|
```toml
|
|
[crio.runtime.runtimes.kata-qemu]
|
|
runtime_path = "/usr/bin/kata-runtime"
|
|
runtime_type = "oci"
|
|
|
|
[crio.runtime.runtimes.kata-fc]
|
|
runtime_path = "/usr/bin/kata-runtime"
|
|
runtime_type = "oci"
|
|
```
|
|
|
|
|
|
### containerd
|
|
|
|
To customize containerd to select Kata Containers runtime, follow our
|
|
"Configure containerd to use Kata Containers" internal documentation
|
|
[here](../how-to/how-to-use-k8s-with-cri-containerd-and-kata.md#configure-containerd-to-use-kata-containers).
|
|
|
|
## Install Kubernetes
|
|
|
|
Depending on what your needs are and what you expect to do with Kubernetes,
|
|
please refer to the following
|
|
[documentation](https://kubernetes.io/docs/setup/) to install it correctly.
|
|
|
|
Kubernetes talks with CRI implementations through a `container-runtime-endpoint`,
|
|
also called CRI socket. This socket path is different depending on which CRI
|
|
implementation you chose, and the Kubelet service has to be updated accordingly.
|
|
|
|
### Configure for CRI-O
|
|
|
|
`/etc/systemd/system/kubelet.service.d/0-crio.conf`
|
|
```
|
|
[Service]
|
|
Environment="KUBELET_EXTRA_ARGS=--container-runtime=remote --runtime-request-timeout=15m --container-runtime-endpoint=unix:///var/run/crio/crio.sock"
|
|
```
|
|
|
|
### Configure for containerd
|
|
|
|
`/etc/systemd/system/kubelet.service.d/0-cri-containerd.conf`
|
|
```
|
|
[Service]
|
|
Environment="KUBELET_EXTRA_ARGS=--container-runtime=remote --runtime-request-timeout=15m --container-runtime-endpoint=unix:///run/containerd/containerd.sock"
|
|
```
|
|
For more information about containerd see the "Configure Kubelet to use containerd"
|
|
documentation [here](../how-to/how-to-use-k8s-with-cri-containerd-and-kata.md#configure-kubelet-to-use-containerd).
|
|
|
|
## Run a Kubernetes pod with Kata Containers
|
|
|
|
After you update your Kubelet service based on the CRI implementation you
|
|
are using, reload and restart Kubelet. Then, start your cluster:
|
|
```bash
|
|
$ sudo systemctl daemon-reload
|
|
$ sudo systemctl restart kubelet
|
|
|
|
# If using CRI-O
|
|
$ sudo kubeadm init --ignore-preflight-errors=all --cri-socket /var/run/crio/crio.sock --pod-network-cidr=10.244.0.0/16
|
|
|
|
# If using containerd
|
|
$ sudo kubeadm init --ignore-preflight-errors=all --cri-socket /run/containerd/containerd.sock --pod-network-cidr=10.244.0.0/16
|
|
|
|
$ export KUBECONFIG=/etc/kubernetes/admin.conf
|
|
```
|
|
|
|
You can force Kubelet to use Kata Containers by adding some `untrusted`
|
|
annotation to your pod configuration. In our case, this ensures Kata
|
|
Containers is the selected runtime to run the described workload.
|
|
|
|
`nginx-untrusted.yaml`
|
|
```yaml
|
|
apiVersion: v1
|
|
kind: Pod
|
|
metadata:
|
|
name: nginx-untrusted
|
|
annotations:
|
|
io.kubernetes.cri.untrusted-workload: "true"
|
|
spec:
|
|
containers:
|
|
- name: nginx
|
|
image: nginx
|
|
```
|
|
|
|
Next, you run your pod:
|
|
```
|
|
$ sudo -E kubectl apply -f nginx-untrusted.yaml
|
|
```
|
|
|