diff --git a/vars/ubuntu-20.04.yml b/vars/ubuntu-20.04.yml
index f1b8d832..4f04e72a 100644
--- a/vars/ubuntu-20.04.yml
+++ b/vars/ubuntu-20.04.yml
@@ -25,6 +25,7 @@ _lxc_cache_map:
     - /etc/apt/sources.list
     - /etc/apt/apt.conf.d/
     - /etc/apt/trusted.gpg.d/
+    - /etc/apt/trusted.gpg
     - /etc/apt/preferences.d/
     - /etc/environment
     - /etc/localtime