= Contributing to OpenShift
OpenShift Developers <dev@lists.openshift.redhat.com>
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The OpenShift architecture builds upon the flexibility and scalability of https://docker.com/[Docker] and https://github.com/kubernetes/kubernetes[Kubernetes] to deliver a powerful new https://www.youtube.com/watch?v=aZ40GobvA1c[Platform-as-a-Service] system. This article explains how to set up a development environment and get involved with this latest version of OpenShift. Kubernetes is included in this repo for ease of development, and the version we include is periodically updated.
To get started you can either:
* <<download-from-github>>
Or if you are interested in development, start with:
* <<openshift-development>> and choose between:
** <<develop-locally-on-your-host>>
** <<develop-on-virtual-machine-using-vagrant>>
== Download from GitHub
The OpenShift team periodically publishes binaries to GitHub on https://github.com/openshift/origin/releases[the Releases page]. These are Linux, Windows, or Mac OS X 64bit binaries (note that Mac and Windows are client only). You'll need Docker installed on your local system (see https://docs.docker.com/installation/[the installation page] if you've never installed Docker before).
The tar file for each platform contains a single binary `openshift` which is the all-in-one OpenShift installation.
* Use `sudo openshift start` to launch the server. Root access is required to create services due to the need to modify IPTables. See issue: https://github.com/kubernetes/kubernetes/issues/1859.
* Use `oc login <server> ...` to connect to an OpenShift server
* Use `openshift help` to see more about the commands in the binary
== OpenShift Development
To get started, https://help.github.com/articles/fork-a-repo[fork] the https://github.com/openshift/origin[origin repo].
=== Develop locally on your host
You can develop OpenShift 3 on Windows, Mac, or Linux, but you'll need Docker installed on Linux to actually launch containers.
* For OpenShift 3 development, install the http://golang.org/[Go] programming language
* To launch containers, install the https://docker.com/[Docker] platform
Here's how to get set up:
1. For Go, Git and optionally also Docker, follow the links below to get to installation information for these tools: +
** http://golang.org/doc/install[Installing Go]. You must install Go 1.4 and NOT use $HOME/go directory for Go installation.
** http://git-scm.com/book/en/v2/Getting-Started-Installing-Git[Installing Git]
** https://docs.docker.com/installation/[Installing Docker]. NOTE: OpenShift requires Docker 1.7.1 or higher.
2. Next, create a Go workspace directory: +
+
----
$ mkdir $HOME/go
----
3. In your `.bashrc` file or `.bash_profile` file, set a GOPATH and update your PATH: +
+
----
export GOPATH=$HOME/go
export PATH=$PATH:$GOPATH/bin
----
4. Open up a new terminal or source the changes in your current terminal. Then clone this repo:
$ mkdir -p $GOPATH/src/github.com/openshift
$ cd $GOPATH/src/github.com/openshift
$ git clone git://github.com/<forkid>/origin # Replace <forkid> with the your github id
$ cd origin
$ git remote add upstream git://github.com/openshift/origin
5. From here, you can generate the OpenShift binaries by running:
$ make clean build
6. Next, assuming you have not changed the kubernetes/openshift service subnet configuration from the default value of 172.30.0.0/16, you need to instruct the Docker daemon to trust any Docker registry on the 172.30.0.0/16 subnet. If you are running Docker as a service via `systemd`, add the `--insecure-registry 172.30.0.0/16` argument to the options value in `/etc/sysconfig/docker` and restart the Docker daemon. Otherwise, add "--insecure-registry 172.30.0.0/16" to the Docker daemon invocation, eg:
$ docker -d --insecure-registry 172.30.0.0/16
7. Then, the OpenShift firewalld rules are also a work in progress. For now it is easiest to disable firewalld altogether:
$ sudo systemctl stop firewalld
8. Firewalld will start again on your next reboot, but you can manually restart it with this command when you are done running OpenShift:
$ sudo systemctl start firewalld
9. Now change into the directory with the OpenShift binaries, and start the OpenShift server:
$ cd _output/local/bin/linux/amd64
$ sudo ./openshift start
+
NOTE: Replace "linux/amd64" with the appropriate value for your platform/architecture.
10. Launch another terminal, change into the same directory you started OpenShift, and deploy the private docker registry within OpenShift with the following commands (note, the --credentials option allows secure communication between the internal OpenShift Docker registry and the OpenShift server, and the --config option provides your identity (in this case, cluster-admin) to the OpenShift server):
$ sudo chmod +r openshift.local.config/master/openshift-registry.kubeconfig
$ sudo chmod +r openshift.local.config/master/admin.kubeconfig
$ oadm registry --create --credentials=openshift.local.config/master/openshift-registry.kubeconfig --config=openshift.local.config/master/admin.kubeconfig
11. If it is not there already, add the current directory to the $PATH, so you can leverage the OpenShift commands elsewhere.
12. You are now ready to edit the source, rebuild and restart OpenShift to test your changes.
13. NOTE: to properly stop OpenShift and clean up, so that you can start fresh instance of OpenShift, execute:
$ sudo pkill -x openshift
$ docker ps | awk 'index($NF,"k8s_")==1 { print $1 }' | xargs -l -r docker stop
$ mount | grep "openshift.local.volumes" | awk '{ print $3}' | xargs -l -r sudo umount
$ cd <to the dir you ran openshift start> ; sudo rm -rf openshift.local.*
=== Develop on virtual machine using Vagrant
To facilitate rapid development we've put together a Vagrantfile you can use to stand up a development environment.
1. http://www.vagrantup.com/downloads[Install Vagrant]
2. https://www.virtualbox.org/wiki/Downloads[Install VirtualBox] (Ex: `yum install VirtualBox` from the RPM Fusion repository)
3. Clone the project and change into the directory:
$ mkdir -p $GOPATH/src/github.com/openshift
$ cd $GOPATH/src/github.com/openshift
$ git clone git://github.com/<forkid>/origin # Replace <forkid> with the your github id
$ cd origin
$ git remote add upstream git://github.com/openshift/origin
4. Bring up the VM (If you are new to Vagrant, consider http://docs.vagrantup.com[Vagrant Docs] for help on items like provider selection. Also consider the enablement of your hardware's virtualization extensions, such as https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/6/html/Virtualization_Administration_Guide/sect-Virtualization-Troubleshooting-Enabling_Intel_VT_and_AMD_V_virtualization_hardware_extensions_in_BIOS.html[RHEL] for example.). Also note, for the `make clean build` in step 6 to work, a sufficient amount of memory needs to be allocated for the VM, where that amount of memory is not necessarily needed if you are not doing a compile, but simply running openshift (and hence is not set as the default):
$ export OPENSHIFT_MEMORY=2096
$ vagrant up
5. SSH in:
$ vagrant ssh
6. Run a build in SSH:
$ cd /data/src/github.com/openshift/origin
$ make clean build
7. Now change into the directory with the OpenShift binaries, and start the OpenShift server:
$ cd _output/local/bin/linux/amd64
$ sudo ./openshift start --public-master=localhost --volume-dir=</absolute/path> &> openshift.log &
+
NOTE: By default your origin directory will be mounted as a vagrant synced folder into `/data/src/github.com/openshift/origin`, but it is advised to use a different directory for volume storage than the one for the origin directory vagrant synced folder. Hence in the above example of the `openshift start` command invocation the `--volume-dir=</absolute/path>` option is supplied.
8. On your host system, try browsing to: https://localhost:8443/console
9. Deploy the private docker registry within OpenShift with the following commands (note, the --credentials option allows secure communication between the internal OpenShift Docker registry and the OpenShift server, and the --config option provides your identity (in this case, cluster-admin) to the OpenShift server):
$ sudo chmod +r openshift.local.config/master/openshift-registry.kubeconfig
$ sudo chmod +r openshift.local.config/master/admin.kubeconfig
$ ./oadm registry --create --credentials=openshift.local.config/master/openshift-registry.kubeconfig --config=openshift.local.config/master/admin.kubeconfig
10. You are now ready to edit the source, rebuild and restart OpenShift to test your changes.
11. NOTE: to properly stop OpenShift and clean up, so that you can start fresh instance of OpenShift, execute:
$ sudo pkill openshift
$ docker ps | awk 'index($NF,"k8s_")==1 { print $1 }' | xargs -l -r docker stop
$ mount | grep "openshift.local.volumes" | awk '{ print $3}' | xargs -l -r sudo umount
$ cd <to the dir you ran openshift start> ; sudo rm -rf openshift.local.*
$ mount | grep < "\/absolute\/path", where that is the value passed to the `--volume-dir` argument on openshift start > | awk '{ print $3}' | xargs -l -r sudo umount
$ sudo rm -rf < "\/absolute\/path", where again that is the value passed to the `--volume-dir`argument >
TIP: To ensure you get the latest image. First run `vagrant box remove fedora_inst`. And if later on you employ a dev cluster, additionally run `vagrant box remove fedora_deps`.
TIP: See https://github.com/openshift/vagrant-openshift for more advanced options
==== Ensure virtual box interfaces are not managed by Network Manager
If you are developing on a Linux host, then you need to ensure that Network Manager is ignoring the
virtual box interfaces, otherwise they cause issues with multi-vm networking.
Follow these steps to ensure that virtual box interfaces are unmanaged:
1. Check the status of Network Manager devices:
$ nmcli d
2. If any devices whose name start with vboxnet* are not unmanaged, then they need to be added to
NetworkManager configuration to be ignored.
$ cat /etc/NetworkManager/NetworkManager.conf
[keyfile]
unmanaged-devices=mac:0a:00:27:00:00:00;mac:0a:00:27:00:00:01;mac:0a:00:27:00:00:02
3. One can use the following command to help generate the configuration:
$ ip link list | grep vboxnet -A 1 | grep link/ether | awk '{print "mac:" $2}' | paste -sd ";" -
4. Reload the Network Manager configuration:
$ sudo nmcli con reload
=== Develop and test using a docker-in-docker cluster
It's possible to run an OpenShift multinode cluster on a single host
via docker-in-docker (dind). Cluster creation is cheaper since each
node is a container instead of a VM. This was implemented primarily
to support multinode network testing, but may prove useful for other
use cases.
To run a dind cluster in a VM, follow steps 1-3 of the Vagrant
instructions and then execute the following:
$ export OPENSHIFT_DIND_DEV_CLUSTER=true
$ vagrant up
Bringing up the VM for the first time will take a while due to the
overhead of package installation, building docker images, and building
openshift. Assuming the 'vagrant up' command completes without error,
a dind OpenShift cluster should now be running on the VM. To access
the cluster, login to the VM:
$ vagrant ssh
Once on the VM, the 'oc' and 'openshift' commands can be used to
interact with the cluster:
$ oc get nodes
It's also possible to login to the participating containers
(openshift-master, openshift-node-1, openshift-node-2, etc) via docker
exec:
$ docker exec -ti openshift-master bash
While it is possible to manage the OpenShift daemon in the containers
(supervisorctl {start,stop,restart} [daemon name]), dind cluster
management is fast enough that the suggested approach is to manage at
the cluster level instead.
Invoking the dind-cluster.sh script without arguments will provide a
usage message:
Usage: hack/dind-cluster.sh {start|stop|restart|...}
Additional documentation of how a dind cluster is managed can be found
at the top of the dind-cluster.sh script.
Attempting to start a cluster when one is already running will result
in an error message from docker indicating that the named containers
already exist. To redeploy a cluster after making changes, use the
'start' and 'stop' or 'restart' commands. OpenShift is always built
as part of the dind cluster deployment initiated by 'start' or
'restart'.
By default the cluster will consist of a master and 2 nodes. The
NUM_MINIONS environment variable can be used to override the default
of 2 nodes.
Containers are torn down on stop and restart, but the root of the
origin repo is mounted to /data in each container to allow for a
persistent installation target.
While it is possible to run a dind cluster on any host (not just a
vagrant VM), it is recommended to consider the warnings at the top of
the dind-cluster.sh script.
==== Testing networking with docker-in-docker
It's possible to run networking tests against a running
docker-in-docker cluster (i.e. 'hack/dind-cluster.sh start' has
already been invoked):
$ hack/dind-cluster.sh test-net-e2e
Since a cluster can only be configured with a single network plugin at
a time, this method of invoking the networking tests will only
validate the active plugin. It is possible to target all plugins via
the following command:
$ test/extended/networking.sh
networking.sh creates a new dind cluster for each networking plugin,
runs the tests against that cluster, and then tears down the cluster.
The test dind clusters are isolated from any user-created clusters,
and test output and artifacts of the most recent test run are retained
in /tmp/openshift-extended-tests/networking.
Whether using dind-cluster.sh or networking.sh to run tests, it's
possible to override the default test regexes via the
NETWORKING_E2E_FOCUS and NETWORKING_E2E_SKIP environment variables.
These variables set the '-focus' and '-skip' arguments supplied to the
https://github.com/onsi/ginkgo[ginkgo] test runner.
==== Running Kubernetes e2e tests
It's possible to target the Kubernetes e2e tests against a running
OpenShift cluster. From the root of an origin repo:
$ pushd ..
$ git clone http://github.com/kubernetes/kubernetes/
$ pushd kubernetes/build
$ ./run hack/build-go.sh
$ popd && popd
$ export KUBE_ROOT=../kubernetes
$ hack/test-kube-e2e.sh --ginkgo.focus="[regex]"
The previous sequence of commands will target a vagrant-based
OpenShift cluster whose configuration is stored in the default
location in the origin repo. To target a dind cluster, an additional
environment variable needs to be set before invoking test-kube-e2e.sh:
$ export OS_CONF_ROOT=/tmp/openshift-dind-cluster/openshift
== Development: What's on the Menu?
Right now you can see what's happening with OpenShift development at:
https://github.com/openshift/origin[github.com/openshift/origin]
Ready to play with some code? Hop down and read up on our link:#_the_roadmap[roadmap] for ideas on where you can contribute.
*If you are interested in contributing to Kubernetes directly:* +
https://github.com/kubernetes/kubernetes#community-discussion-and-support[Join the Kubernetes community] and check out the https://github.com/kubernetes/kubernetes/blob/master/CONTRIBUTING.md[contributing guide].
== Troubleshooting
If you run into difficulties running OpenShift, start by reading through the https://github.com/openshift/origin/blob/master/docs/debugging-openshift.md[troubleshooting guide].
== The Roadmap
The OpenShift project roadmap lives https://trello.com/b/nlLwlKoz/atomicopenshift-roadmap[on Trello]. Of particular interest to those who want to get involved with the OpenShift 3 architecture are the following topics:
* https://trello.com/c/uqNIamJi[Orchestration]
* https://trello.com/c/ja8bbQwy[Networking]
* https://trello.com/c/3zHeVSla[Routing and Load Balancing]
These link to active and backlog tasks that the OpenShift team is planning or working on for Kubernetes development.
== Stay in Touch
Reach out to the OpenShift team and other community contributors through IRC and our mailing list:
* IRC: Hop onto the http://webchat.freenode.net/?randomnick=1&channels=openshift-dev&uio=d4[#openshift-dev] channel on http://www.freenode.net/[FreeNode].
* E-mail: Join the OpenShift developers' http://lists.openshift.redhat.com/openshiftmm/listinfo/dev[mailing list].