diff --git a/roles/firewall/tasks/config.yml b/roles/firewall/tasks/config.yml
index 89c4204..8a0ea1b 100644
--- a/roles/firewall/tasks/config.yml
+++ b/roles/firewall/tasks/config.yml
@@ -44,9 +44,9 @@
   authorized_key: "user=root key={{ master_key.stdout }}"
 
 - name: Get my host SSH key
-  command: cat /etc/ssh/ssh_host_ed25519_key.pub
+  slurp:
+    src: /etc/ssh/ssh_host_ed25519_key.pub
   register: node_key
-  changed_when: false
 
 - name: Introduce myself to master
   delegate_to: '{{ master }}'
@@ -56,4 +56,4 @@
   become_flags: "-s /bin/sh" # no login shell for user
   known_hosts:
     name: "{{ inventory_hostname }}"
-    key: "{{ inventory_hostname }},{{ interfaces | selectattr('name', '==', 'lo') | map(attribute='ip_addresses') | first | selectattr('role') | selectattr('role.value', '==', 'loopback') | map(attribute='address') | ipv4 | first | ipaddr('address') }} {{ node_key.stdout }}" # TODO make IP retrieval less terrifying
+    key: "{{ inventory_hostname }},{{ interfaces | selectattr('name', '==', 'lo') | map(attribute='ip_addresses') | first | selectattr('role') | selectattr('role.value', '==', 'loopback') | map(attribute='address') | ipv4 | first | ipaddr('address') }} {{ node_key.content | b64decode }}" # TODO make IP retrieval less terrifying