first commit

dns/README.md

@@ -0,0 +1,21 @@
+## Setup AdGuard Sync credentials
+```bash
+kubectl create secret generic adguardhome-password \ 
+    --from-literal=password='your_adguardhome_password' \ 
+    --from-literal=username='your_adguardhome_username' -n dns
+```
+
+## Add AdGuardHome to CoreDNS configmap fallback:
+1. Edit the CoreDNS configmap:
+```bash
+kubectl edit configmap coredns -n kube-system
+```
+2. Replace the `forward` line with the following:
+```
+    forward . <ADGUARDHOME_IP> <ADGUARDHOME_IP_2>
+```
+This will use AdGuardHome as the primary DNS server and a secondary one as a fallback, instead of using the default Kubernetes CoreDNS server.
+
+You may also use `/etc/resolv.conf` to forward to the node's own DNS resolver, but it depends on whether it's well configured or not. *Since it's Linux, we never know.*
+
+Ideally, since DNS is required for fetching the container image, you would have AdGuardHome as first and then a public DNS server as second (fallback).