diff --git a/roles/juju-setup/tasks/main.yml b/roles/juju-setup/tasks/main.yml
index 53eaf2e..4a59c76 100644
--- a/roles/juju-setup/tasks/main.yml
+++ b/roles/juju-setup/tasks/main.yml
@@ -36,7 +36,7 @@
 
 - name: Have VM's use the apt-cache
   command: ansible services -m lineinfile -a "dest=/etc/apt/apt.conf.d/02apt-cacher-ng
-    mode=0644 owner=root group=root regexp='^Acquire' line='Acquire::http { Proxy \"http://{{ apt_cacher_name }}:{{ apt_cacher_port }}\"; };'"
+    mode=0644 owner=root group=root regexp='^Acquire' line='Acquire::http { Proxy \"http://{{ apt_cacher_name }}:{{ apt_cacher_port | default('3142') }}\"; };'"
 
 - name: Update software in all the VMs
   command: ansible services -m apt -b -u ubuntu -a "upgrade=dist update_cache=yes cache_valid_time=3600"