diff --git a/tools/dockerfile/distribtest/python_fedora20_x64/Dockerfile b/tools/dockerfile/distribtest/python_fedora20_x64/Dockerfile
index d58036410f6de6f304afe3479f8a315a7903e1e5..502c81c7cb07623c18311f37672315bf50e16802 100644
--- a/tools/dockerfile/distribtest/python_fedora20_x64/Dockerfile
+++ b/tools/dockerfile/distribtest/python_fedora20_x64/Dockerfile
@@ -30,3 +30,8 @@
 FROM fedora:20
 
 RUN yum clean all && yum update -y && yum install -y python python-pip
+
+# Upgrading six would fail because of docker issue when using overlay.
+# Trying twice makes it work fine.
+# https://github.com/docker/docker/issues/10180
+RUN pip2 install --upgrade six || pip2 install --upgrade six
diff --git a/tools/dockerfile/distribtest/python_fedora21_x64/Dockerfile b/tools/dockerfile/distribtest/python_fedora21_x64/Dockerfile
index 1eb4c1e77501639017b9d9e212145e2adfdcd900..f1b0e2f4b223634ee6ad232202fdbc71d4579989 100644
--- a/tools/dockerfile/distribtest/python_fedora21_x64/Dockerfile
+++ b/tools/dockerfile/distribtest/python_fedora21_x64/Dockerfile
@@ -35,3 +35,8 @@ FROM fedora:21
 RUN yum install -y yum-plugin-ovl
 
 RUN yum clean all && yum update -y && yum install -y python python-pip
+
+# Upgrading six would fail because of docker issue when using overlay.
+# Trying twice makes it work fine.
+# https://github.com/docker/docker/issues/10180
+RUN pip2 install --upgrade six || pip2 install --upgrade six