Ecosyste.ms: Awesome
An open API service indexing awesome lists of open source software.
https://github.com/flatcar/flatcar-linux-update-operator
A Kubernetes operator to manage updates of Flatcar Container Linux
https://github.com/flatcar/flatcar-linux-update-operator
flatcar kinvolk kubernetes operator
Last synced: 3 months ago
JSON representation
A Kubernetes operator to manage updates of Flatcar Container Linux
- Host: GitHub
- URL: https://github.com/flatcar/flatcar-linux-update-operator
- Owner: flatcar
- License: apache-2.0
- Created: 2019-08-02T12:12:15.000Z (over 5 years ago)
- Default Branch: master
- Last Pushed: 2023-07-24T17:39:22.000Z (over 1 year ago)
- Last Synced: 2024-11-16T01:19:32.806Z (3 months ago)
- Topics: flatcar, kinvolk, kubernetes, operator
- Language: Go
- Homepage:
- Size: 60.2 MB
- Stars: 102
- Watchers: 15
- Forks: 19
- Open Issues: 77
-
Metadata Files:
- Readme: README.md
- Changelog: CHANGELOG.md
- License: LICENSE
- Code of conduct: code-of-conduct.md
Awesome Lists containing this project
README
# Flatcar Linux Update Operator
Flatcar Linux Update Operator is a node reboot controller for Kubernetes running
Flatcar Container Linux images. When a reboot is needed after updating the system via
[update_engine](https://github.com/coreos/update_engine), the operator will
drain the node before rebooting it.
Flatcar Linux Update Operator fulfills the same purpose as
[locksmith](https://github.com/coreos/locksmith), but has better integration
with Kubernetes by explicitly marking a node as unschedulable and deleting pods
on the node before rebooting.
## Design
Flatcar Linux Update Operator is divided into two parts: `update-operator` and `update-agent`.
`update-agent` runs as a DaemonSet on each node, waiting for a `UPDATE_STATUS_UPDATED_NEED_REBOOT` signal via D-Bus from `update_engine`.
It will indicate via [node annotations](./pkg/constants/constants.go) that it needs a reboot.
`update-operator` runs as a Deployment, watching changes to node annotations and reboots the nodes as needed.
It coordinates the reboots of multiple nodes in the cluster, ensuring that not too many are rebooting at once.
Currently, `update-operator` only reboots one node at a time.
## Requirements
- A Kubernetes cluster (>= 1.6) running on Flatcar Container Linux
- The `update-engine.service` systemd unit on each machine should be unmasked, enabled and started in systemd
- The `locksmithd.service` systemd unit on each machine should be masked and stopped in systemd
To unmask a service, run `systemctl unmask `.
To enable a service, run `systemctl enable `.
To start/stop a service, run `systemctl start ` or `systemctl stop ` respectively.
or using a [Container Linux Config](https://www.flatcar.org/docs/latest/provisioning/cl-config/) file:
```
systemd:
units:
- name: locksmithd.service
mask: true
- name: update-engine.service
enabled: true
```
## Usage
Create the `update-operator` deployment and `update-agent` daemonset.
```
kubectl kustomize examples/deploy | kubectl apply -f-
```
## Test
To test that it is working, you can SSH to a node and trigger an update check by running `update_engine_client -check_for_update` or simulate a reboot is needed by running `locksmithctl send-need-reboot`.
You can also annotate one of your nodes using the command below. Shortly after, you should see the Node being drained as a preparation for the reboot.
```sh
export NODE=""
kubectl annotate node $NODE --overwrite \
flatcar-linux-update.v1.flatcar-linux.net/reboot-needed="true"
```