diff --git a/env/Dockerfile b/env/Dockerfile
index 80f085007..26e8a66df 100644
--- a/env/Dockerfile
+++ b/env/Dockerfile
@@ -1,8 +1,6 @@
 # vim: syntax=dockerfile
 
-# Bionic Beaver (18.04) does not require ppa repositories for any packages
-# we need, such as g++-7, clang-6.0, ansible, grpc, etc.
-ARG BASE_IMAGE=ubuntu:bionic
+ARG BASE_IMAGE=ubuntu:focal
 FROM ${BASE_IMAGE}
 
 RUN echo "APT::Install-Recommends false;" >> /etc/apt/apt.conf.d/00recommends && \
@@ -21,7 +19,7 @@ RUN apt-get -q update && \
 	apt-get purge -y ansible && \
 	apt-get autoremove -y && \
 	rm -rf /var/lib/apt/lists
-
+RUN update-alternatives --install /usr/local/bin/python python /usr/bin/python3 3
 RUN mkdir -p /build/bess
 
 # Build DPDK testpmd (used in bessctl samples)
diff --git a/env/rebuild_images.py b/env/rebuild_images.py
index a7c540e84..be9caf16e 100755
--- a/env/rebuild_images.py
+++ b/env/rebuild_images.py
@@ -40,7 +40,7 @@
 TARGET_REPO = 'nefelinetworks/bess_build'
 
 imgs = {
-    'bionic64': {'base': 'ubuntu:bionic', 'tag_suffix': ''},
+    'focal64': {'base': 'ubuntu:focal', 'tag_suffix': ''},
 }