Fix local dns in docker

ansible_playbooks/setup-cluster.yml

@@ -58,11 +58,12 @@
 
     # If DNS is broken after dnsmasq, then need to set /etc/resolv.conf to something
     # pointing to 127.0.0.1 and possibly restart Docker and Nomad
+    # Actually, we should point to our external Nomad address so that Docker uses it
     - name: Update resolv.conf
       lineinfile:
         dest: /etc/resolv.conf
         create: true
-        line: "nameserver 127.0.0.1"
+        line: "nameserver {{ hostvars[inventory_hostname]['ansible_default_ipv4']['address'] }}"
       become: true
 
 - name: Setup Vault cluster