Clear Containers in Zun

Zun now supports running Clear Containers with regular Docker containers. Clear containers run containers as very lightweight virtual machines which boot up really fast and has low memory footprints. It provides security to the containers with an isolated environment. You can read more about Clear Containers here.

Installation with DevStack

It is possible to run Clear Containers with Zun. Follow the Developer Quick-Start to download DevStack, Zun code and copy the local.conf file. Now perform the following steps to install Clear Containers with DevStack:

cd /opt/stack/devstack
echo "ENABLE_CLEAR_CONTAINER=true" >> local.conf

Verify the installation by:

$ sudo docker info | grep Runtimes
Runtimes: cor runc

Using Clear Containers with Zun

To create Clear Containers with Zun, specify the –runtime option:

zun run --name clear-container --runtime cor cirros ping -c 4


Clear Containers support in Zun is not production ready. It is recommended not to running Clear Containers and runc containers on the same host.