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diff --git a/tutorial.md b/tutorial.md new file mode 100644 index 000000000..2b48c21ca --- /dev/null +++ b/tutorial.md @@ -0,0 +1,425 @@ +# CRI-O Tutorial + +This tutorial will walk you through the installation of [CRI-O](https://github.com/kubernetes-incubator/cri-o), an Open Container Initiative-based implementation of [Kubernetes Container Runtime Interface](https://github.com/kubernetes/community/blob/master/contributors/design-proposals/node/container-runtime-interface-v1.md), and the creation of [Redis](https://redis.io/) server running in a [Pod](http://kubernetes.io/docs/user-guide/pods/). + +## Prerequisites + +A Linux machine is required to download and build the `CRI-O` components and run the commands in this tutorial. + +Create a machine running Ubuntu 16.10: + +``` +gcloud compute instances create cri-o \ + --machine-type n1-standard-2 \ + --image-family ubuntu-1610 \ + --image-project ubuntu-os-cloud +``` + +SSH into the machine: + +``` +gcloud compute ssh cri-o +``` + +## Installation + +This section will walk you through installing the following components: + +* crio - The implementation of the Kubernetes CRI, which manages Pods. +* crioctl - The crio client for testing. +* cni - The Container Network Interface +* runc - The OCI runtime to launch the container + + +### runc + +Download the `runc` release binary: + +``` +wget https://github.com/opencontainers/runc/releases/download/v1.0.0-rc4/runc.amd64 +``` + +Set the executable bit and copy the `runc` binary into your PATH: + +``` +chmod +x runc.amd64 +``` + +``` +sudo mv runc.amd64 /usr/bin/runc +``` + +Print the `runc` version: + +``` +runc -version +``` +``` +runc version 1.0.0-rc4 +commit: 2e7cfe036e2c6dc51ccca6eb7fa3ee6b63976dcd +spec: 1.0.0 +``` + +### crio + +The `crio` project does not ship binary releases so you'll need to build it from source. + +#### Install the Go runtime and tool chain + +Download the Go 1.7.4 binary release: + +``` +wget https://storage.googleapis.com/golang/go1.7.4.linux-amd64.tar.gz +``` + +Install Go 1.7.4: + +``` +sudo tar -xvf go1.7.4.linux-amd64.tar.gz -C /usr/local/ +``` + +``` +mkdir -p $HOME/go/src +``` + +``` +export GOPATH=$HOME/go +``` + +``` +export PATH=$PATH:/usr/local/go/bin:$GOPATH/bin +``` + +At this point the Go 1.7.4 tool chain should be installed: + +``` +go version +``` + +``` +go version go1.7.4 linux/amd64 +``` + +#### Build crio from source + +``` +sudo apt-get install -y libglib2.0-dev libseccomp-dev libapparmor-dev +``` + +``` +go get -d github.com/kubernetes-incubator/cri-o +``` + +``` +cd $GOPATH/src/github.com/kubernetes-incubator/cri-o +``` + +``` +make install.tools +``` + +``` +make +``` + +``` +sudo make install +``` + +Output: + +``` +install -D -m 755 kpod /usr/local/bin/kpod +install -D -m 755 crio /usr/local/bin/crio +install -D -m 755 crioctl /usr/local/bin/crioctl +install -D -m 755 conmon/conmon /usr/local/libexec/crio/conmon +install -D -m 755 pause/pause /usr/local/libexec/crio/pause +install -d -m 755 /usr/local/share/man/man{1,5,8} +install -m 644 docs/kpod.1 docs/kpod-launch.1 -t /usr/local/share/man/man1 +install -m 644 docs/crio.conf.5 -t /usr/local/share/man/man5 +install -m 644 docs/crio.8 -t /usr/local/share/man/man8 +install -D -m 644 crio.conf /etc/crio/crio.conf +install -D -m 644 seccomp.json /etc/crio/seccomp.json +``` + +If you are installing for the first time, generate config as follows: + +``` +sudo make install.config +``` + +Output: + +``` +install -D -m 644 crio.conf /etc/crio/crio.conf +install -D -m 644 seccomp.json /etc/crio/seccomp.json +``` + +#### Start the crio system daemon + +``` +sudo sh -c 'echo "[Unit] +Description=OCI-based implementation of Kubernetes Container Runtime Interface +Documentation=https://github.com/kubernetes-incubator/cri-o + +[Service] +ExecStart=/usr/local/bin/crio --log-level debug +Restart=on-failure +RestartSec=5 + +[Install] +WantedBy=multi-user.target" > /etc/systemd/system/crio.service' +``` + +``` +sudo systemctl daemon-reload +``` +``` +sudo systemctl enable crio +``` +``` +sudo systemctl start crio +``` + +#### Ensure the crio service is running + +``` +sudo crioctl runtimeversion +``` +``` +VersionResponse: Version: 0.1.0, RuntimeName: runc, RuntimeVersion: 1.0.0-rc4, RuntimeApiVersion: v1alpha1 +``` + +### CNI plugins + +This tutorial will use the latest version of `CNI` plugins from the master branch and build it from source. + +Download the `CNI` plugins source tree: + +``` +go get -d github.com/containernetworking/plugins +``` + +``` +cd $GOPATH/src/github.com/containernetworking/plugins +``` + +Build the `CNI` plugins: + +``` +./build.sh +``` + +Output: + +``` +Building API +Building reference CLI +Building plugins + flannel + tuning + bridge + ipvlan + loopback + macvlan + ptp + dhcp + host-local + noop +``` + +Install the `CNI` plugins: + +``` +sudo mkdir -p /opt/cni/bin +``` + +``` +sudo cp bin/* /opt/cni/bin/ +``` + +#### Configure CNI + +``` +sudo mkdir -p /etc/cni/net.d +``` + +``` +sudo sh -c 'cat >/etc/cni/net.d/10-mynet.conf <<-EOF +{ + "cniVersion": "0.2.0", + "name": "mynet", + "type": "bridge", + "bridge": "cni0", + "isGateway": true, + "ipMasq": true, + "ipam": { + "type": "host-local", + "subnet": "10.88.0.0/16", + "routes": [ + { "dst": "0.0.0.0/0" } + ] + } +} +EOF' +``` + +``` +sudo sh -c 'cat >/etc/cni/net.d/99-loopback.conf <<-EOF +{ + "cniVersion": "0.2.0", + "type": "loopback" +} +EOF' +``` + +At this point `CNI` is installed and configured to allocation IP address to containers from the `10.88.0.0/16` subnet. + +## Pod Tutorial + +Now that the `CRI-O` components have been installed and configured we are ready to create a Pod. This section will walk you through launching a Redis server in a Pod. Once the Redis server is running we'll use telnet to verify it's working, then we'll stop the Redis server and clean up the Pod. + +### Creating a Pod + +First we need to setup a Pod sandbox using a Pod configuration, which can be found in the `cri-o` source tree: + +``` +cd $GOPATH/src/github.com/kubernetes-incubator/cri-o +``` + +Next create the Pod and capture the Pod ID for later use: + +``` +POD_ID=$(sudo crioctl pod run --config test/testdata/sandbox_config.json) +``` + +> sudo crioctl pod run --config test/testdata/sandbox_config.json + +Use the `crioctl` command to get the status of the Pod: + +``` +sudo crioctl pod status --id $POD_ID +``` + +Output: + +``` +ID: cd6c0883663c6f4f99697aaa15af8219e351e03696bd866bc3ac055ef289702a +Name: podsandbox1 +UID: redhat-test-crio +Namespace: redhat.test.crio +Attempt: 1 +Status: SANDBOX_READY +Created: 2016-12-14 15:59:04.373680832 +0000 UTC +Network namespace: /var/run/netns/cni-bc37b858-fb4d-41e6-58b0-9905d0ba23f8 +IP Address: 10.88.0.2 +Labels: + group -> test +Annotations: + owner -> hmeng + security.alpha.kubernetes.io/seccomp/pod -> unconfined + security.alpha.kubernetes.io/sysctls -> kernel.shm_rmid_forced=1,net.ipv4.ip_local_port_range=1024 65000 + security.alpha.kubernetes.io/unsafe-sysctls -> kernel.msgmax=8192 +``` + +### Create a Redis container inside the Pod + +Use the `crioctl` command to pull the redis image, create a redis container from a container configuration and attach it to the Pod created earlier: + +``` +sudo crioctl image pull redis:alpine +CONTAINER_ID=$(sudo crioctl ctr create --pod $POD_ID --config test/testdata/container_redis.json) +``` + +> sudo crioctl ctr create --pod $POD_ID --config test/testdata/container_redis.json + +The `crioctl ctr create` command will take a few seconds to return because the redis container needs to be pulled. + +Start the Redis container: + +``` +sudo crioctl ctr start --id $CONTAINER_ID +``` + +Get the status for the Redis container: + +``` +sudo crioctl ctr status --id $CONTAINER_ID +``` + +Output: + +``` +ID: d0147eb67968d81aaddbccc46cf1030211774b5280fad35bce2fdb0a507a2e7a +Name: podsandbox1-redis +Status: CONTAINER_RUNNING +Created: 2016-12-14 16:00:42.889089352 +0000 UTC +Started: 2016-12-14 16:01:56.733704267 +0000 UTC +``` + +### Test the Redis container + +Connect to the Pod IP on port 6379: + +``` +telnet 10.88.0.2 6379 +``` + +``` +Trying 10.88.0.2... +Connected to 10.88.0.2. +Escape character is '^]'. +``` + +At the prompt type `MONITOR`: + +``` +Trying 10.88.0.2... +Connected to 10.88.0.2. +Escape character is '^]'. +MONITOR ++OK +``` + +Exit the telnet session by typing `ctrl-]` and `quit` at the prompt: + +``` +^] + +telnet> quit +Connection closed. +``` + +#### Viewing the Redis logs + +The Redis logs are logged to the stderr of the crio service, which can be viewed using `journalctl`: + +``` +sudo journalctl -u crio --no-pager +``` + +### Stop the redis container and delete the Pod + +``` +sudo crioctl ctr stop --id $CONTAINER_ID +``` + +``` +sudo crioctl ctr remove --id $CONTAINER_ID +``` + +``` +sudo crioctl pod stop --id $POD_ID +``` + +``` +sudo crioctl pod remove --id $POD_ID +``` + +``` +sudo crioctl pod list +``` + +``` +sudo crioctl ctr list +``` |