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diff --git a/doc/articles/openshift_and_gitlab/index.md b/doc/articles/openshift_and_gitlab/index.md index c0bbcfe2a8a..b7594cfef7f 100644 --- a/doc/articles/openshift_and_gitlab/index.md +++ b/doc/articles/openshift_and_gitlab/index.md @@ -1,510 +1 @@ -# Getting started with OpenShift Origin 3 and GitLab - -> **Article [Type](../../development/writing_documentation.html#types-of-technical-articles):** tutorial || -> **Level:** intermediary || -> **Author:** [Achilleas Pipinellis](https://gitlab.com/axil) || -> **Publication date:** 2016-06-28 - -## Introduction - -[OpenShift Origin][openshift] is an open source container application -platform created by [RedHat], based on [kubernetes] and [Docker]. That means -you can host your own PaaS for free and almost with no hassle. - -In this tutorial, we will see how to deploy GitLab in OpenShift using GitLab's -official Docker image while getting familiar with the web interface and CLI -tools that will help us achieve our goal. - ---- - -## Prerequisites - -OpenShift 3 is not yet deployed on RedHat's offered Online platform ([openshift.com]), -so in order to test it, we will use an [all-in-one Virtualbox image][vm] that is -offered by the OpenShift developers and managed by Vagrant. If you haven't done -already, go ahead and install the following components as they are essential to -test OpenShift easily: - -- [VirtualBox] -- [Vagrant] -- [OpenShift Client][oc] (`oc` for short) - -It is also important to mention that for the purposes of this tutorial, the -latest Origin release is used: - -- **oc** `v1.3.0` (must be [installed][oc-gh] locally on your computer) -- **openshift** `v1.3.0` (is pre-installed in the [VM image][vm-new]) -- **kubernetes** `v1.3.0` (is pre-installed in the [VM image][vm-new]) - ->**Note:** -If you intend to deploy GitLab on a production OpenShift cluster, there are some -limitations to bare in mind. Read on the [limitations](#current-limitations) -section for more information and follow the linked links for the relevant -discussions. - -Now that you have all batteries, let's see how easy it is to test OpenShift -on your computer. - -## Getting familiar with OpenShift Origin - -The environment we are about to use is based on CentOS 7 which comes with all -the tools needed pre-installed: Docker, kubernetes, OpenShift, etcd. - -### Test OpenShift using Vagrant - -As of this writing, the all-in-one VM is at version 1.3, and that's -what we will use in this tutorial. - -In short: - -1. Open a terminal and in a new directory run: - ```sh - vagrant init openshift/origin-all-in-one - ``` -1. This will generate a Vagrantfile based on the all-in-one VM image -1. In the same directory where you generated the Vagrantfile - enter: - - ```sh - vagrant up - ``` - -This will download the VirtualBox image and fire up the VM with some preconfigured -values as you can see in the Vagrantfile. As you may have noticed, you need -plenty of RAM (5GB in our example), so make sure you have enough. - -Now that OpenShift is setup, let's see how the web console looks like. - -### Explore the OpenShift web console - -Once Vagrant finishes its thing with the VM, you will be presented with a -message which has some important information. One of them is the IP address -of the deployed OpenShift platform and in particular <https://10.2.2.2:8443/console/>. -Open this link with your browser and accept the self-signed certificate in -order to proceed. - -Let's login as admin with username/password `admin/admin`. This is what the -landing page looks like: - - - -You can see that a number of [projects] are already created for testing purposes. - -If you head over the `openshift-infra` project, a number of services with their -respective pods are there to explore. - - - -We are not going to explore the whole interface, but if you want to learn about -the key concepts of OpenShift, read the [core concepts reference][core] in the -official documentation. - -### Explore the OpenShift CLI - -OpenShift Client (`oc`), is a powerful CLI tool that talks to the OpenShift API -and performs pretty much everything you can do from the web UI and much more. - -Assuming you have [installed][oc] it, let's explore some of its main -functionalities. - -Let's first see the version of `oc`: - -```sh -$ oc version - -oc v1.3.0 -kubernetes v1.3.0+52492b4 -``` - -With `oc help` you can see the top level arguments you can run with `oc` and -interact with your cluster, kubernetes, run applications, create projects and -much more. - -Let's login to the all-in-one VM and see how to achieve the same results like -when we visited the web console earlier. The username/password for the -administrator user is `admin/admin`. There is also a test user with username/ -password `user/user`, with limited access. Let's login as admin for the moment: - -```sh -$ oc login https://10.2.2.2:8443 - -Authentication required for https://10.2.2.2:8443 (openshift) -Username: admin -Password: -Login successful. - -You have access to the following projects and can switch between them with 'oc project <projectname>': - - * cockpit - * default (current) - * delete - * openshift - * openshift-infra - * sample - -Using project "default". -``` - -Switch to the `openshift-infra` project with: - -```sh -oc project openshift-infra -``` - -And finally, see its status: - -```sh -oc status -``` - -The last command should spit a bunch of information about the statuses of the -pods and the services, which if you look closely is what we encountered in the -second image when we explored the web console. - -You can always read more about `oc` in the [OpenShift CLI documentation][oc]. - -### Troubleshooting the all-in-one VM - -Using the all-in-one VM gives you the ability to test OpenShift whenever you -want. That means you get to play with it, shutdown the VM, and pick up where -you left off. - -Sometimes though, you may encounter some issues, like OpenShift not running -when booting up the VM. The web UI may not responding or you may see issues -when trying to login with `oc`, like: - -``` -The connection to the server 10.2.2.2:8443 was refused - did you specify the right host or port? -``` - -In that case, the OpenShift service might not be running, so in order to fix it: - -1. SSH into the VM by going to the directory where the Vagrantfile is and then - run: - - ```sh - vagrant ssh - ``` - -1. Run `systemctl` and verify by the output that the `openshift` service is not - running (it will be in red color). If that's the case start the service with: - - ```sh - sudo systemctl start openshift - ``` - -1. Verify the service is up with: - - ```sh - systemctl status openshift -l - ``` - -Now you will be able to login using `oc` (like we did before) and visit the web -console. - -## Deploy GitLab - -Now that you got a taste of what OpenShift looks like, let's deploy GitLab! - -### Create a new project - -First, we will create a new project to host our application. You can do this -either by running the CLI client: - -```bash -$ oc new-project gitlab -``` - -or by using the web interface: - - - -If you used the command line, `oc` automatically uses the new project and you -can see its status with: - -```sh -$ oc status - -In project gitlab on server https://10.2.2.2:8443 - -You have no services, deployment configs, or build configs. -Run 'oc new-app' to create an application. -``` - -If you visit the web console, you can now see `gitlab` listed in the projects list. - -The next step is to import the OpenShift template for GitLab. - -### Import the template - -The [template][templates] is basically a JSON file which describes a set of -related object definitions to be created together, as well as a set of -parameters for those objects. - -The template for GitLab resides in the Omnibus GitLab repository under the -docker directory. Let's download it locally with `wget`: - -```bash -wget https://gitlab.com/gitlab-org/omnibus-gitlab/raw/master/docker/openshift-template.json -``` - -And then let's import it in OpenShift: - -```bash -oc create -f openshift-template.json -n openshift -``` - ->**Note:** -The `-n openshift` namespace flag is a trick to make the template available to all -projects. If you recall from when we created the `gitlab` project, `oc` switched -to it automatically, and that can be verified by the `oc status` command. If -you omit the namespace flag, the application will be available only to the -current project, in our case `gitlab`. The `openshift` namespace is a global -one that the administrators should use if they want the application to be -available to all users. - -We are now ready to finally deploy GitLab! - -### Create a new application - -The next step is to use the template we previously imported. Head over to the -`gitlab` project and hit the **Add to Project** button. - - - -This will bring you to the catalog where you can find all the pre-defined -applications ready to deploy with the click of a button. Search for `gitlab` -and you will see the previously imported template: - - - -Select it, and in the following screen you will be presented with the predefined -values used with the GitLab template: - - - -Notice at the top that there are three resources to be created with this -template: - -- `gitlab-ce` -- `gitlab-ce-redis` -- `gitlab-ce-postgresql` - -While PostgreSQL and Redis are bundled in Omnibus GitLab, the template is using -separate images as you can see from [this line][line] in the template. - -The predefined values have been calculated for the purposes of testing out -GitLab in the all-in-one VM. You don't need to change anything here, hit -**Create** to start the deployment. - -If you are deploying to production you will want to change the **GitLab instance -hostname** and use greater values for the volume sizes. If you don't provide a -password for PostgreSQL, it will be created automatically. - ->**Note:** -The `gitlab.apps.10.2.2.2.xip.io` hostname that is used by default will -resolve to the host with IP `10.2.2.2` which is the IP our VM uses. It is a -trick to have distinct FQDNs pointing to services that are on our local network. -Read more on how this works in <http://xip.io>. - -Now that we configured this, let's see how to manage and scale GitLab. - -## Manage and scale GitLab - -Setting up GitLab for the first time might take a while depending on your -internet connection and the resources you have attached to the all-in-one VM. -GitLab's docker image is quite big (~500MB), so you'll have to wait until -it's downloaded and configured before you use it. - -### Watch while GitLab gets deployed - -Navigate to the `gitlab` project at **Overview**. You can notice that the -deployment is in progress by the orange color. The Docker images are being -downloaded and soon they will be up and running. - - - -Switch to the **Browse > Pods** and you will eventually see all 3 pods in a -running status. Remember the 3 resources that were to be created when we first -created the GitLab app? This is where you can see them in action. - - - -You can see GitLab being reconfigured by taking look at the logs in realtime. -Click on `gitlab-ce-2-j7ioe` (your ID will be different) and go to the **Logs** -tab. - - - -At a point you should see a _**gitlab Reconfigured!**_ message in the logs. -Navigate back to the **Overview** and hopefully all pods will be up and running. - - - -Congratulations! You can now navigate to your new shinny GitLab instance by -visiting <http://gitlab.apps.10.2.2.2.xip.io> where you will be asked to -change the root user password. Login using `root` as username and providing the -password you just set, and start using GitLab! - -### Scale GitLab with the push of a button - -If you reach to a point where your GitLab instance could benefit from a boost -of resources, you'd be happy to know that you can scale up with the push of a -button. - -In the **Overview** page just click the up arrow button in the pod where -GitLab is. The change is instant and you can see the number of [replicas] now -running scaled to 2. - - - -Upping the GitLab pods is actually like adding new application servers to your -cluster. You can see how that would work if you didn't use GitLab with -OpenShift by following the [HA documentation][ha] for the application servers. - -Bare in mind that you may need more resources (CPU, RAM, disk space) when you -scale up. If a pod is in pending state for too long, you can navigate to -**Browse > Events** and see the reason and message of the state. - - - -### Scale GitLab using the `oc` CLI - -Using `oc` is super easy to scale up the replicas of a pod. You may want to -skim through the [basic CLI operations][basic-cli] to get a taste how the CLI -commands are used. Pay extra attention to the object types as we will use some -of them and their abbreviated versions below. - -In order to scale up, we need to find out the name of the replication controller. -Let's see how to do that using the following steps. - -1. Make sure you are in the `gitlab` project: - - ```sh - oc project gitlab - ``` - -1. See what services are used for this project: - - ```sh - oc get svc - ``` - - The output will be similar to: - - ``` - NAME CLUSTER-IP EXTERNAL-IP PORT(S) AGE - gitlab-ce 172.30.243.177 <none> 22/TCP,80/TCP 5d - gitlab-ce-postgresql 172.30.116.75 <none> 5432/TCP 5d - gitlab-ce-redis 172.30.105.88 <none> 6379/TCP 5d - ``` - -1. We need to see the replication controllers of the `gitlab-ce` service. - Get a detailed view of the current ones: - - ```sh - oc describe rc gitlab-ce - ``` - - This will return a large detailed list of the current replication controllers. - Search for the name of the GitLab controller, usually `gitlab-ce-1` or if - that failed at some point and you spawned another one, it will be named - `gitlab-ce-2`. - -1. Scale GitLab using the previous information: - - ```sh - oc scale --replicas=2 replicationcontrollers gitlab-ce-2 - ``` - -1. Get the new replicas number to make sure scaling worked: - - ```sh - oc get rc gitlab-ce-2 - ``` - - which will return something like: - - ``` - NAME DESIRED CURRENT AGE - gitlab-ce-2 2 2 5d - ``` - -And that's it! We successfully scaled the replicas to 2 using the CLI. - -As always, you can find the name of the controller using the web console. Just -click on the service you are interested in and you will see the details in the -right sidebar. - - - -### Autoscaling GitLab - -In case you were wondering whether there is an option to autoscale a pod based -on the resources of your server, the answer is yes, of course there is. - -We will not expand on this matter, but feel free to read the documentation on -OpenShift's website about [autoscaling]. - -## Current limitations - -As stated in the [all-in-one VM][vm] page: - -> By default, OpenShift will not allow a container to run as root or even a -non-random container assigned userid. Most Docker images in the Dockerhub do not -follow this best practice and instead run as root. - -The all-in-one VM we are using has this security turned off so it will not -bother us. In any case, it is something to keep in mind when deploying GitLab -on a production cluster. - -In order to deploy GitLab on a production cluster, you will need to assign the -GitLab service account to the `anyuid` Security Context. - -1. Edit the Security Context: - ```sh - oc edit scc anyuid - ``` - -1. Add `system:serviceaccount:<project>:gitlab-ce-user` to the `users` section. - If you changed the Application Name from the default the user will - will be `<app-name>-user` instead of `gitlab-ce-user` - -1. Save and exit the editor - -## Conclusion - -By now, you should have an understanding of the basic OpenShift Origin concepts -and a sense of how things work using the web console or the CLI. - -GitLab was hard to install in previous versions of OpenShift, -but now that belongs to the past. Upload a template, create a project, add an -application and you are done. You are ready to login to your new GitLab instance. - -And remember that in this tutorial we just scratched the surface of what Origin -is capable of. As always, you can refer to the detailed -[documentation][openshift-docs] to learn more about deploying your own OpenShift -PaaS and managing your applications with the ease of containers. - -[RedHat]: https://www.redhat.com/en "RedHat website" -[openshift]: https://www.openshift.org "OpenShift Origin website" -[vm]: https://www.openshift.org/vm/ "OpenShift All-in-one VM" -[vm-new]: https://atlas.hashicorp.com/openshift/boxes/origin-all-in-one "Official OpenShift Vagrant box on Atlas" -[template]: https://gitlab.com/gitlab-org/omnibus-gitlab/blob/master/docker/openshift-template.json "OpenShift template for GitLab" -[openshift.com]: https://openshift.com "OpenShift Online" -[kubernetes]: http://kubernetes.io/ "Kubernetes website" -[Docker]: https://www.docker.com "Docker website" -[oc]: https://docs.openshift.org/latest/cli_reference/get_started_cli.html "Documentation - oc CLI documentation" -[VirtualBox]: https://www.virtualbox.org/wiki/Downloads "VirtualBox downloads" -[Vagrant]: https://www.vagrantup.com/downloads.html "Vagrant downloads" -[projects]: https://docs.openshift.org/latest/dev_guide/projects.html "Documentation - Projects overview" -[core]: https://docs.openshift.org/latest/architecture/core_concepts/index.html "Documentation - Core concepts of OpenShift Origin" -[templates]: https://docs.openshift.org/latest/architecture/core_concepts/templates.html "Documentation - OpenShift templates" -[old-post]: https://blog.openshift.com/deploy-gitlab-openshift/ "Old post - Deploy GitLab on OpenShift" -[line]: https://gitlab.com/gitlab-org/omnibus-gitlab/blob/658c065c8d022ce858dd63eaeeadb0b2ddc8deea/docker/openshift-template.json#L239 "GitLab - OpenShift template" -[oc-gh]: https://github.com/openshift/origin/releases/tag/v1.3.0 "Openshift 1.3.0 release on GitHub" -[ha]: http://docs.gitlab.com/ce/administration/high_availability/gitlab.html "Documentation - GitLab High Availability" -[replicas]: https://docs.openshift.org/latest/architecture/core_concepts/deployments.html#replication-controllers "Documentation - Replication controller" -[autoscaling]: https://docs.openshift.org/latest/dev_guide/pod_autoscaling.html "Documentation - Autoscale" -[basic-cli]: https://docs.openshift.org/latest/cli_reference/basic_cli_operations.html "Documentation - Basic CLI operations" -[openshift-docs]: https://docs.openshift.org "OpenShift documentation" +This document was moved to [another location](../../install/openshift_and_gitlab/index.html). |