virtc

README

virtc

virtc is a simple command-line tool that serves to demonstrate typical usage of the virt API. This is example software; unlike other projects like runc, runv, or rkt, virt is not a full container runtime.

Virtc example

Here we explain how to use the pod API from virtc command line.

Prepare your environment

Get your kernel

Fedora

$ sudo -E dnf config-manager --add-repo http://download.opensuse.org/repositories/home:clearlinux:preview:clear-containers-2.0/Fedora_24/home:clearlinux:preview:clear-containers-2.0.repo
$ sudo dnf install linux-container 

Ubuntu

$ sudo sh -c "echo 'deb http://download.opensuse.org/repositories/home:/clearlinux:/preview:/clear-containers-2.0/xUbuntu_16.04/ /' >> /etc/apt/sources.list.d/cc-oci-runtime.list"
$ sudo apt install linux-container

Get your image

It has to be a recent Clear Linux image to make sure it contains hyperstart binary. You can dowload the following tested image, or any version more recent.

$ wget https://download.clearlinux.org/releases/11130/clear/clear-11130-containers.img.xz
$ unxz clear-11130-containers.img.xz
$ sudo cp clear-11130-containers.img /usr/share/clear-containers/clear-containers.img

Get virtc

Download virtc

$ go get github.com/containers/virtcontainers

Build virtc

$ cd $GOPATH/src/github.com/containers/virtcontainers
$ cd virtc && go build

Run virtc

All following commands needs to be run as root. Currently, virtc only starts single container pods.

Create your container bundle

As an example we will create a busybox bundle:

$ mkdir -p /tmp/bundles/busybox/
$ docker pull busybox
$ cd /tmp/bundles/busybox/
$ mkdir rootfs
$ docker export $(docker create busybox) | tar -C rootfs -xvf -
$ echo -e '#!/bin/sh\ncd "\"\n"sh"' > rootfs/.containerexec
$ echo -e 'HOME=/root\nPATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin\nTERM=xterm' > rootfs/.containerenv

Run a new pod (Create + Start)

./virtc pod run --bundle="/tmp/bundles/busybox/rootfs" --agent="hyperstart" --init-cmd="/bin/sh"

Create a new pod

./virtc pod create --bundle="/tmp/bundles/busybox/rootfs" --agent="hyperstart" --init-cmd="/bin/sh"

This should generate that kind of output

Created pod 306ecdcf-0a6f-4a06-a03e-86a7b868ffc8

Start an existing pod

./virtc pod start --id=306ecdcf-0a6f-4a06-a03e-86a7b868ffc8

Stop an existing pod

./virtc pod stop --id=306ecdcf-0a6f-4a06-a03e-86a7b868ffc8

Get the status of an existing pod and its containers

./virtc pod status --id=306ecdcf-0a6f-4a06-a03e-86a7b868ffc8

This should generate the following output:

POD ID                                  STATE   HYPERVISOR      AGENT
306ecdcf-0a6f-4a06-a03e-86a7b868ffc8    running qemu            hyperstart

CONTAINER ID    STATE
1               ready

Delete an existing pod

./virtc pod delete --id=306ecdcf-0a6f-4a06-a03e-86a7b868ffc8

List all existing pods

./virtc pod list

This should generate that kind of output

POD ID                                  STATE   HYPERVISOR      AGENT
306ecdcf-0a6f-4a06-a03e-86a7b868ffc8    running qemu            hyperstart
92d73f74-4514-4a0d-81df-db1cc4c59100    running qemu            hyperstart
7088148c-049b-4be7-b1be-89b3ae3c551c    ready   qemu            hyperstart
6d57654e-4804-4a91-b72d-b5fe375ed3e1    ready   qemu            hyperstart