* Users should deploy the Container Linux Update Operator to coordinate reboots of Container Linux nodes in a Kubernetes cluster * Write cluster addon docs to describe CLUO * Terraform modules `bootkube` and `profiles` (Kubernetes) disable locksmithd
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Cluster Addons
Kubernetes clusters run cluster addons atop Kubernetes itself. Addons may be considered essential for bootstrapping (non-optional), important (highly recommended), or optional.
Essential
Several addons are considered essential. CoreOS cluster creation tools ensure these addons are included. Kubernetes clusters deployed via the Matchbox examples or using our Terraform Modules include these addons as well.
kube-proxy
kube-proxy is deployed as a DaemonSet.
kube-dns
kube-dns is deployed as a Deployment.
Important
Container Linux Update Operator
The Container Linux Update Operator (i.e. CLUO) coordinates reboots of auto-updating Container Linux nodes so that one node reboots at a time and nodes are drained before reboot. CLUO enables the auto-update behavior Container Linux clusters are known for, but does it in a Kubernetes native way. Deploying CLUO is strongly recommended.
Create the update-operator deployment and update-agent DaemonSet.
kubectl apply -f examples/addons/cluo/update-operator.yaml
kubectl apply -f examples/addons/cluo/update-agent.yaml
Note, CLUO replaces locksmithd reboot coordination. The update_engine systemd unit on hosts still performs the Container Linux update check, download, and install to the inactive partition.