talos/website/content/docs/v0.7/Guides/upgrading-kubernetes.md
Andrew Rynhard 8338daf086 fix: use ghcr.io/talos-systems/kubelet
Moves us off of docker.io.

Signed-off-by: Andrew Rynhard <andrew@rynhard.io>
2020-11-11 08:44:07 -08:00

264 lines
5.1 KiB
Markdown

---
title: Upgrading Kubernetes
---
## Video Walkthrough
To see a live demo of this writeup, see the video below:
<iframe width="560" height="315" src="https://www.youtube.com/embed/sw78qS8vBGc" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>
## Kubeconfig
In order to edit the control plane, we will need a working `kubectl` config.
If you don't already have one, you can get one by running:
```bash
talosctl --nodes <master node> kubeconfig
```
### Automated Kubernetes Upgrade
To upgrade from Kubernetes v1.18.6 to v1.19.0 run:
```bash
$ talosctl --nodes <master node> upgrade-k8s --from 1.18.6 --to 1.19.0
updating pod-checkpointer grace period to "0m"
sleeping 5m0s to let the pod-checkpointer self-checkpoint be updated
temporarily taking "kube-apiserver" out of pod-checkpointer control
updating daemonset "kube-apiserver" to version "1.19.0"
updating daemonset "kube-controller-manager" to version "1.19.0"
updating daemonset "kube-scheduler" to version "1.19.0"
updating daemonset "kube-proxy" to version "1.19.0"
updating pod-checkpointer grace period to "5m0s"
```
### Manual Kubernetes Upgrade
Kubernetes can be upgraded manually as well by following the steps outlined below.
They are equivalent to the steps performed by the `talosctl upgrade-k8s` command.
#### pod-checkpointer
Talos runs `pod-checkpointer` component which helps to recover control plane components (specifically, API server) if control plane is not healthy.
However, the way checkpoints interact with API server upgrade may make an upgrade take a lot longer due to a race condition on API server listen port.
In order to speed up upgrades, first lower `pod-checkpointer` grace period to zero (`kubectl -n kube-system edit daemonset pod-checkpointer`), change:
```yaml
kind: DaemonSet
...
spec:
...
template:
...
spec:
containers:
- name: pod-checkpointer
command:
...
- --checkpoint-grace-period=5m0s
```
to:
```yaml
kind: DaemonSet
...
spec:
...
template:
...
spec:
containers:
- name: pod-checkpointer
command:
...
- --checkpoint-grace-period=0s
```
Wait for 5 minutes to let `pod-checkpointer` update self-checkpoint to the new grace period.
#### API Server
In the API server's `DaemonSet`, change:
```yaml
kind: DaemonSet
...
spec:
...
template:
...
spec:
containers:
- name: kube-apiserver
image: ...
command:
- ./hyperkube
- kube-apiserver
```
to:
```yaml
kind: DaemonSet
...
spec:
...
template:
...
spec:
containers:
- name: kube-apiserver
image: k8s.gcr.io/kube-apiserver:v1.19.0
command:
- /go-runner
- /usr/local/bin/kube-apiserver
```
To edit the `DaemonSet`, run:
```bash
kubectl edit daemonsets -n kube-system kube-apiserver
```
#### Controller Manager
In the controller manager's `DaemonSet`, change:
```yaml
kind: DaemonSet
...
spec:
...
template:
...
spec:
containers:
- name: kube-controller-manager
image: ...
command:
- ./hyperkube
- kube-controller-manager
```
to:
```yaml
kind: DaemonSet
...
spec:
...
template:
...
spec:
containers:
- name: kube-controller-manager
image: k8s.gcr.io/kube-controller-manager:v1.19.0
command:
- /go-runner
- /usr/local/bin/kube-controller-manager
```
To edit the `DaemonSet`, run:
```bash
kubectl edit daemonsets -n kube-system kube-controller-manager
```
#### Scheduler
In the scheduler's `DaemonSet`, change:
```yaml
kind: DaemonSet
...
spec:
...
template:
...
spec:
containers:
- name: kube-scheduler
image: ...
command:
- ./hyperkube
- kube-scheduler
```
to:
```yaml
kind: DaemonSet
...
spec:
...
template:
...
spec:
containers:
- name: kube-sceduler
image: k8s.gcr.io/kube-scheduler:v1.19.0
command:
- /go-runner
- /usr/local/bin/kube-scheduler
```
To edit the `DaemonSet`, run:
```bash
kubectl edit daemonsets -n kube-system kube-scheduler
```
#### Restoring pod-checkpointer
Restore grace period of 5 minutes (`kubectl -n kube-system edit daemonset pod-checkpointer`), change:
```yaml
kind: DaemonSet
...
spec:
...
template:
...
spec:
containers:
- name: pod-checkpointer
command:
...
- --checkpoint-grace-period=0s
```
to:
```yaml
kind: DaemonSet
...
spec:
...
template:
...
spec:
containers:
- name: pod-checkpointer
command:
...
- --checkpoint-grace-period=5m0s
```
### Kubelet
The Talos team now maintains an image for the `kubelet` that should be used starting with Kubernetes 1.19.
The image for this release is `ghcr.io/talos-systems/kubelet:v1.19.3`.
To explicitly set the image, we can use the [official documentation](/v0.7/en/configuration/v1alpha1#kubelet).
For example:
```yaml
machine:
...
kubelet:
image: ghcr.io/talos-systems/kubelet:v1.19.3
```