Add fleetlock docs and links to addons

* Add links to fleetlock for Fedora CoreOS reboot coordination
* https://github.com/poseidon/fleetlock

CHANGES.md

@@ -14,6 +14,7 @@ Notable changes between versions.
 
 ### Addons
 
+* Introduce [fleetlock](https://github.com/poseidon/fleetlock) for Fedora CoreOS reboot coordination ([#814](https://github.com/poseidon/typhoon/pull/814))
 * Update Grafana from v7.1.3 to [v7.1.5](https://github.com/grafana/grafana/releases/tag/v7.1.5)
 
 ## v1.18.8

docs/addons/fleetlock.md

@@ -0,0 +1,39 @@
+## fleetlock
+
+[fleetlock](https://github.com/poseidon/fleetlock) is a reboot coordinator for Fedora CoreOS nodes. It implements the [FleetLock](https://github.com/coreos/airlock/pull/1/files) protocol for use as a [Zincati](https://github.com/coreos/zincati) lock [strategy](https://github.com/coreos/zincati/blob/master/docs/usage/updates-strategy.md) backend.
+
+Declare a Zincati `fleet_lock` strategy when provisioning Fedora CoreOS nodes via [snippets](/advanced/customization/#hosts).
+
+```yaml
+variant: fcos
+version: 1.0.0
+storage:
+  files:
+    - path: /etc/zincati/config.d/55-update-strategy.toml
+      contents:
+        inline: |
+          [updates]
+          strategy = "fleet_lock"
+          [updates.fleet_lock]
+          base_url = "http://10.3.0.15/"
+```
+
+```tf
+module "nemo" {
+  ...
+  controller_snippets = [
+    file("./snippets/zincati-strategy.yaml"),
+  ]
+  worker_snippets = [
+    file("./snippets/zincati-strategy.yaml"),
+  ]
+}
+```
+
+Apply fleetlock based on the example manifests.
+
+```sh
+git clone git@github.com:poseidon/fleetlock.git
+kubectl apply -f examples/k8s
+```
+

docs/addons/overview.md

@@ -1,8 +1,9 @@
 # Addons
 
-Every Typhoon cluster is verified to work well with several post-install addons.
+Typhoon clusters are verified to work well with several post-install addons.
 
 * Nginx [Ingress Controller](ingress.md)
 * [Prometheus](prometheus.md)
 * [Grafana](grafana.md)
+* [fleetlock](fleetlock.md)
 

docs/architecture/operating-systems.md

@@ -16,10 +16,10 @@ Together, they diversify Typhoon to support a range of container technologies.
 
 | Property          | Flatcar Linux | Fedora CoreOS |
 |-------------------|---------------------------------|---------------|
-| Kernel            | ~4.19.x | ~5.5.x |
+| Kernel            | ~4.19.x | ~5.7.x |
 | systemd           | 241 | 243 |
 | Ignition system   | Ignition v2.x spec | Ignition v3.x spec |
-| Container Engine  | docker 18.06.3-ce  | docker 18.09.8 |
+| Container Engine  | docker 18.06.3-ce  | docker 19.03.11 |
 | storage driver    | overlay2 (extfs)  | overlay2 (xfs) |
 | logging driver    | json-file | journald |
 | cgroup driver     | cgroupfs (except Flatcar edge) | systemd  |
@@ -37,8 +37,8 @@ Together, they diversify Typhoon to support a range of container technologies.
 | control plane images | upstream images | upstream images |
 | on-host etcd      | rkt-fly   | podman |
 | on-host kubelet   | rkt-fly   | podman |
-| CNI plugins       | calico or flannel | calico or flannel |
-| coordinated drain & OS update | [CLUO](https://github.com/coreos/container-linux-update-operator) addon | (planned) |
+| CNI plugins       | calico, cilium, flannel | calico, cilium, flannel |
+| coordinated drain & OS update | [FLUO](https://github.com/kinvolk/flatcar-linux-update-operator) addon | [fleetlock](https://github.com/poseidon/fleetlock) |
 
 ## Directory Locations
 

mkdocs.yml

@@ -82,3 +82,4 @@ nav:
     - 'Nginx Ingress': 'addons/ingress.md'
     - 'Prometheus': 'addons/prometheus.md'
     - 'Grafana': 'addons/grafana.md'
+    - 'fleetlock': 'addons/fleetlock.md'