diff --git a/cookbooks/docker/install.rb b/cookbooks/docker/install.rb
index 050e460..5839d2e 100644
--- a/cookbooks/docker/install.rb
+++ b/cookbooks/docker/install.rb
@@ -11,7 +11,7 @@ end
 execute 'add-apt-repository \
    "deb [arch=amd64] https://download.docker.com/linux/ubuntu \
    $(lsb_release -cs) \
-   stable"' do
+   stable" -y' do
   not_if 'which docker'
 end