Add Mastodon review

Signed-off-by: David Young <davidy@funkypenguin.co.nz>

manuscript/kubernetes/persistence/index.md

@@ -7,5 +7,5 @@ Here are some popular options, ranked in difficulty/complexity, in vaguely ascen
 * [Local Path Provisioner](/kubernetes/persistence/local-path-provisioner/) (on k3s)
 * [TopoLVM](/kubernetes/persistence/topolvm/)
 * OpenEBS (coming soon)
-* Rook Ceph (coming soon)
+* [Rook Ceph](/kubernetes/persistence/rook-ceph/)
 * Longhorn (coming soon)

manuscript/kubernetes/persistence/rook-ceph.md

@@ -1,3 +1,53 @@
-# Rook Ceph
+---
+title: How to use Rook Ceph for Persistent Storage in Kubernetes
+description: How to deploy Rook Ceph into your Kubernetes cluster for persistent storage
+---
 
-Coming soon!
+# Persistent storage in Kubernetes with Rook Ceph / CephFS
+
+[Ceph](https://docs.ceph.com/en/quincy/) is a highly-reliable, scalable network storage platform which uses individual disks across participating nodes to provide fault-tolerant storage.
+
+![Ceph Screenshot](/images/ceph.png){ loading=lazy }
+
+[Rook](https://rook.io) provides an operator for Ceph, decomposing the [10-year-old](https://en.wikipedia.org/wiki/Ceph_(software)#Release_history), at-time-arcane, platform into cloud-native components, created declaratively, whose lifecycle is managed by an operator.
+
+
+## Rook Ceph requirements
+
+!!! summary "Ingredients"
+
+    Already deployed:
+
+    * [x] A [Kubernetes cluster](/kubernetes/cluster/)
+    * [x] [Flux deployment process](/kubernetes/deployment/flux/) bootstrapped
+    * [x] An [Ingress](/kubernetes/ingress/) to route incoming traffic to services  
+
+    New:
+
+    * [ ] At least 3 nodes with dedicated disks available (*more is better*)
+
+## Preparation
+
+### Namespace
+
+We need a namespace to deploy our HelmRelease and associated ConfigMaps into. Per the [flux design](/kubernetes/deployment/flux/), I create this example yaml in my flux repo at `/bootstrap/namespaces/namespace-rook-system.yaml`:
+
+```yaml title="/bootstrap/namespaces/namespace-mastodon.yaml"
+apiVersion: v1
+kind: Namespace
+metadata:
+  name: rook-system
+```
+
+### HelmRepository
+
+```yaml title="/bootstrap/helmrepositories/gitepository-rook-release.yaml"
+apiVersion: source.toolkit.fluxcd.io/v1beta1
+kind: HelmRepository
+metadata:
+  name: rook-release
+  namespace: flux-system
+spec:
+  interval: 15m
+  url: https://charts.rook.io/release
+```