footloose creates containers that look like virtual machines. Those containers run systemd as PID 1 and a ssh daemon that can be used to login into the container. Such "machines" behave very much like a VM, it's even possible to run dockerd in them :)
footloose can be used for a variety of tasks, wherever you'd like virtual machines but want fast boot times or need many of them. An easy way to think about it is: Vagrant, but with containers.
footloose in action:
footloose binaries can be downloaded from the release page:
curl -Lo footloose https://github.com/weaveworks/footloose/releases/download/0.6.3/footloose-0.6.3-linux-x86_64 chmod +x footloose sudo mv footloose /usr/local/bin/On macOS we provide a direct download and a homebrew tap:
curl --silent --location https://github.com/weaveworks/footloose/releases/download/0.6.3/footloose-0.6.3-darwin-x86_64.tar.gz | tar xz sudo mv footloose /usr/local/binor
brew tap weaveworks/tap brew install weaveworks/tap/footlooseAlternatively, build and install footloose from source. It requires having go >= 1.11 installed:
GO111MODULE=on go get github.com/weaveworks/footloosefootloose reads a description of the Cluster of Machines to create from a file, by default named footloose.yaml. An alternate name can be specified on the command line with the --config option or through the FOOTLOOSE_CONFIG environment variable.
The config command helps with creating the initial config file:
# Create a footloose.yaml config file. Instruct we want to create 3 machines. footloose config create --replicas 3Start the cluster:
$ footloose create INFO[0000] Pulling image: quay.io/footloose/centos7 ... INFO[0007] Creating machine: cluster-node0 ... INFO[0008] Creating machine: cluster-node1 ... INFO[0008] Creating machine: cluster-node2 ...It only takes a second to create those machines. The first time
createruns, it will pull the docker image used by thefootloosecontainers so it will take a tiny bit longer.
SSH into a machine with:
$ footloose ssh root@node1 [root@1665288855f6 ~]# ps fx PID TTY STAT TIME COMMAND 1 ? Ss 0:00 /sbin/init 23 ? Ss 0:00 /usr/lib/systemd/systemd-journald 58 ? Ss 0:00 /usr/sbin/sshd -D 59 ? Ss 0:00 \_ sshd: root@pts/1 63 pts/1 Ss 0:00 \_ -bash 82 pts/1 R+ 0:00 \_ ps fx 62 ? Ss 0:00 /usr/lib/systemd/systemd-logindfootloose will default to running a centos 7 container image. The --image argument of config create can be used to configure the OS image. Valid OS images are:
quay.io/footloose/centos7quay.io/footloose/fedora29quay.io/footloose/ubuntu16.04quay.io/footloose/ubuntu18.04quay.io/footloose/amazonlinux2quay.io/footloose/debian10quay.io/footloose/clearlinux
For example:
footloose config create --replicas 3 --image quay.io/footloose/fedora29Ubuntu images need the --privileged flag:
footloose config create --replicas 1 --image quay.io/footloose/ubuntu16.04 --privilegedfootloose config create creates a footloose.yaml configuration file that is then used by subsequent commands such as create, delete or ssh. If desired, the configuration file can be named differently and supplied with the -c, --config option.
$ footloose config create --replicas 3 $ cat footloose.yaml cluster: name: cluster privateKey: cluster-key machines: - count: 3 backend: docker spec: image: quay.io/footloose/centos7 name: node%d portMappings: - containerPort: 22If you want to use Ignite as the backend in order to run real VMs, change to backend: ignite.
cluster: name: cluster privateKey: cluster-key machines: - count: 3 backend: ignite spec: image: weaveworks/ignite-centos:7 name: node%d portMappings: - containerPort: 22 # All Ignite options shown below here are optional and can be omitted. # These are the defaults: ignite: cpus: 2 memory: 1GB diskSize: 4GB kernel: weaveworks/ignite-ubuntu:4.19.47This configuration can naturally be edited by hand. The full list of available parameters are in the reference documentation.
Interesting things can be done with footloose!
- Customize the OS image
- Run Apache
- Specify which ports on the hosts should be bound to services
- Use Ansible to provision machines
- Run Docker inside
footloosemachines! - Isolation and DNS resolution with custom docker networks
- OpenShift with footloose
Under the hood, Container Machines are just containers. They can be inspected with docker:
$ docker ps CONTAINER ID IMAGE COMMAND NAMES 04c27967f76e quay.io/footloose/centos7 "/sbin/init" cluster-node2 1665288855f6 quay.io/footloose/centos7 "/sbin/init" cluster-node1 5134f80b733e quay.io/footloose/centos7 "/sbin/init" cluster-node0The container names are derived from cluster.name and cluster.machines[].name.
They run systemd as PID 1, it's even possible to inspect the boot messages:
$ docker logs cluster-node1 systemd 219 running in system mode. Detected virtualization docker. Detected architecture x86-64. Welcome to CentOS Linux 7 (Core)! Set hostname to <1665288855f6>. Initializing machine ID from random generator. Failed to install release agent, ignoring: File exists [ OK ] Created slice Root Slice. [ OK ] Created slice System Slice. [ OK ] Reached target Slices. [ OK ] Listening on Journal Socket. [ OK ] Reached target Local File Systems. Starting Create Volatile Files and Directories... [ OK ] Listening on Delayed Shutdown Socket. [ OK ] Reached target Swap. [ OK ] Reached target Paths. Starting Journal Service... [ OK ] Started Create Volatile Files and Directories. [ OK ] Started Journal Service. [ OK ] Reached target System Initialization. [ OK ] Started Daily Cleanup of Temporary Directories. [ OK ] Reached target Timers. [ OK ] Listening on D-Bus System Message Bus Socket. [ OK ] Reached target Sockets. [ OK ] Reached target Basic System. Starting OpenSSH Server Key Generation... Starting Cleanup of Temporary Directories... [ OK ] Started Cleanup of Temporary Directories. [ OK ] Started OpenSSH Server Key Generation. Starting OpenSSH server daemon... [ OK ] Started OpenSSH server daemon. [ OK ] Reached target Multi-User System.
In principle yes, but it will also work with Docker container images and on MacOS as well.
We are a very friendly community and love questions, help and feedback.
If you have any questions, feedback, or problems with footloose:
- Check out the examples.
- Join the discussion
- Invite yourself to the Weave community Slack.
- Ask a question on the #footloose Slack channel.
- Join the Weave User Group and get invited to online talks, hands-on training and meetups in your area.
- File an issue.
Your feedback is always welcome!