diff --git a/Dockerfile b/Dockerfile
index eee76c2..074a5ff 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,4 +1,4 @@
-FROM ubuntu:22.04
+FROM ubuntu:20.04
 
 ARG docker_version="20.10.17"
 
diff --git a/Vagrantfile b/Vagrantfile
index 67d7d50..ced906d 100644
--- a/Vagrantfile
+++ b/Vagrantfile
@@ -7,7 +7,14 @@ ENV['VAGRANT_NO_PARALLEL']="true"
 
 Vagrant.configure('2') do |config|
 
-  config.vm.box = "chaifeng/ubuntu-22.04-docker-20.10.17#{(`uname -m`.strip == "arm64")?"-arm64":""}"
+  docker_version = "20.10.17"
+
+  ubuntu_version = File.readlines("Dockerfile").filter { |line|
+    line.start_with?("FROM ")
+  }.first.match(/\d\d\.\d\d/)[0]
+
+  config.vm.box = "chaifeng/ubuntu-#{ubuntu_version}-docker-#{docker_version}#{(`uname -m`.strip == "arm64")?"-arm64":""}"
+
   #config.vm.box = "chaifeng/ubuntu-20.04-docker-20.10.17#{(`uname -m`.strip == "arm64")?"-arm64":""}"
 
   config.vm.provider 'virtualbox' do |vb|
diff --git a/ufw-docker b/ufw-docker
index 5568e11..dffc501 100755
--- a/ufw-docker
+++ b/ufw-docker
@@ -11,7 +11,7 @@ GREP_REGEXP_INSTANCE_NAME="[-_.[:alnum:]]\\+"
 DEFAULT_PROTO=tcp
 
 ufw_docker_agent=ufw-docker-agent
-ufw_docker_agent_image="${UFW_DOCKER_AGENT_IMAGE:-chaifeng/${ufw_docker_agent}:220920-nf_tables}"
+ufw_docker_agent_image="${UFW_DOCKER_AGENT_IMAGE:-chaifeng/${ufw_docker_agent}:221002-legacy}"
 
 if [[ "${ufw_docker_agent_image}" = *-@(legacy|nf_tables) ]]; then
     if iptables --version | grep -F '(legacy)' &>/dev/null; then