From 7e521afe6bacb44f12c50fbe6ec04ac19665fc0a Mon Sep 17 00:00:00 2001
From: Ibrahim Mkusa <ibrahimmkusa@gmail.com>
Date: Wed, 20 Nov 2024 20:54:55 -0500
Subject: [PATCH] Integrate kube-external-dns with pihole for autonomous dns

---
 manifests/external-dns/README.md    | 11 +++++
 manifests/external-dns/install.yaml | 74 +++++++++++++++++++++++++++++
 manifests/pihole/values.yaml        |  5 +-
 3 files changed, 88 insertions(+), 2 deletions(-)
 create mode 100644 manifests/external-dns/README.md
 create mode 100644 manifests/external-dns/install.yaml

diff --git a/manifests/external-dns/README.md b/manifests/external-dns/README.md
new file mode 100644
index 0000000..a92454e
--- /dev/null
+++ b/manifests/external-dns/README.md
@@ -0,0 +1,11 @@
+External DNS with pihole
+
+Make sure to run where `somesecret` will be the password for your pihole
+```
+kubectl create secret generic external-dns-pihole-password \
+  --from-literal EXTERNAL_DNS_PIHOLE_PASSWORD=somesecret
+```
+
+Add the annotation `external-dns.alpha.kubernetes.io/hostname:
+\ nginx.external-dns-test.homelab.local` to your services, so external dns can
+pick up the service and a dns entry in pihole automatically.
diff --git a/manifests/external-dns/install.yaml b/manifests/external-dns/install.yaml
new file mode 100644
index 0000000..2593afd
--- /dev/null
+++ b/manifests/external-dns/install.yaml
@@ -0,0 +1,74 @@
+---
+apiVersion: v1
+kind: ServiceAccount
+metadata:
+  name: external-dns
+---
+apiVersion: rbac.authorization.k8s.io/v1
+kind: ClusterRole
+metadata:
+  name: external-dns
+rules:
+- apiGroups: [""]
+  resources: ["services","endpoints","pods"]
+  verbs: ["get","watch","list"]
+- apiGroups: ["extensions","networking.k8s.io"]
+  resources: ["ingresses"]
+  verbs: ["get","watch","list"]
+- apiGroups: [""]
+  resources: ["nodes"]
+  verbs: ["list","watch"]
+---
+apiVersion: rbac.authorization.k8s.io/v1
+kind: ClusterRoleBinding
+metadata:
+  name: external-dns-viewer
+roleRef:
+  apiGroup: rbac.authorization.k8s.io
+  kind: ClusterRole
+  name: external-dns
+subjects:
+- kind: ServiceAccount
+  name: external-dns
+  namespace: default
+---
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: external-dns
+spec:
+  strategy:
+    type: Recreate
+  selector:
+    matchLabels:
+      app: external-dns
+  template:
+    metadata:
+      labels:
+        app: external-dns
+    spec:
+      serviceAccountName: external-dns
+      containers:
+      - name: external-dns
+        image: registry.k8s.io/external-dns/external-dns:v0.15.0
+        # If authentication is disabled and/or you didn't create
+        # a secret, you can remove this block.
+        envFrom:
+        - secretRef:
+            # Change this if you gave the secret a different name
+            name: external-dns-pihole-password
+        args:
+        - --source=service
+        - --source=ingress
+        # Pihole only supports A/AAAA/CNAME records so there is no mechanism to track ownership.
+        # You don't need to set this flag, but if you leave it unset, you will receive warning
+        # logs when ExternalDNS attempts to create TXT records.
+        - --registry=noop
+        # IMPORTANT: If you have records that you manage manually in Pi-hole, set
+        # the policy to upsert-only so they do not get deleted.
+        - --policy=upsert-only
+        - --provider=pihole
+        # Change this to the actual address of your Pi-hole web server
+        - --pihole-server=http://pihole-web.default.svc.cluster.local
+      securityContext:
+        fsGroup: 65534 # For ExternalDNS to be able to read Kubernetes token files
diff --git a/manifests/pihole/values.yaml b/manifests/pihole/values.yaml
index ae8c2bf..0311c5a 100644
--- a/manifests/pihole/values.yaml
+++ b/manifests/pihole/values.yaml
@@ -118,13 +118,13 @@ serviceWeb:
     nodePort: ""
 
   # -- `spec.type` for the web interface Service
-  type: ClusterIP
+  type: LoadBalancer
 
   # -- `spec.externalTrafficPolicy` for the web interface Service
   externalTrafficPolicy: Local
 
   # -- A fixed `spec.loadBalancerIP` for the web interface Service
-  loadBalancerIP: ""
+  loadBalancerIP: "192.168.0.239"
   # -- A fixed `spec.loadBalancerIP` for the IPv6 web interface Service
   loadBalancerIPv6: ""
 
@@ -404,6 +404,7 @@ regex: {}
 ftl: {}
   # Add values for pihole-FTL.conf
   # MAXDBDAYS: 14
+  #StartLimitBurst: 25
 
 # -- port the container should use to expose HTTP traffic
 webHttp: "80"