It's possible for your source and target branches to diverge, which can result
in the scenario that source branch's pipeline was green, the target's pipeline was green,
but the combined output fails. By having your merge request pipeline automatically
create a new ref that contains the merge result of the source and target branch
(then running a pipeline on that ref), we can better test that the combined result
is also valid.
From GitLab 11.10, pipelines for merge requests run by default
on this merged result. That is, where the source and target branches are combined into a
new ref and a pipeline for this ref validates the result prior to merging.
![Merge request pipeline as the head pipeline](img/merge_request_pipeline.png)
There are some cases where creating a combined ref is not possible or not wanted.
For example, a source branch that has conflicts with the target branch
or a merge request that is still in WIP status. In this case, the merge request pipeline falls back to a "detached" state
and runs on the source branch ref as if it was a regular pipeline.
The detached state serves to warn you that you are working in a situation
subjected to merge problems, and helps to highlight that you should
get out of WIP status or resolve merge conflicts as soon as possible.
![Pipeline's details](img/pipeline_detail.png)
### Enabling combined ref pipelines
This feature disabled by default until we resolve issues with [contention handling](https://gitlab.com/gitlab-org/gitlab-ee/issues/9186). It can be enabled at the project level:
1. Visit your project's **Settings > General** and expand **Merge requests**.
1. Check **Merge pipelines will try to validate the post-merge result prior to merging**.
- This feature requires [GitLab Runner](https://gitlab.com/gitlab-org/gitlab-runner) 11.9 or newer.
- This feature requires [Gitaly](https://gitlab.com/gitlab-org/gitaly) 1.21.0 or newer.
- After the merge request pipeline succeeds, if the target branch has moved forward, the result of the pipeline is stale and must be retried. In busy repos, this can become a problem as it is highly probable that the target branch will have moved ahead. Improvements are [planned](https://gitlab.com/gitlab-org/gitlab-ee/issues/9186) for future versions of GitLab.
- Forking/cross-repo workflows are not currently supported. To follow progress, see [#9713](https://gitlab.com/gitlab-org/gitlab-ee/issues/9713).
- This feature is not available for [fast forward merges](../../user/project/merge_requests/fast_forward_merge.md) yet. To follow progress, see [#58226](https://gitlab.com/gitlab-org/gitlab-ce/issues/58226).
## Excluding certain jobs
...
...
@@ -138,3 +180,12 @@ External users could steal secret variables from the parent project by modifying
We're discussing a secure solution of running pipelines for merge requests
that submitted from forked projects,
see [the issue about the permission extension](https://gitlab.com/gitlab-org/gitlab-ce/issues/23902).
## Additional predefined variables
By using pipelines for merge requests, GitLab exposes additional predefined variables to the pipeline jobs.
Those variables contain information of the associated merge request, so that it's useful
to integrate your job with [GitLab Merge Request API](../../api/merge_requests.md).
You can find the list of avilable variables in [the reference sheet](../variables/predefined_variables.md).
The variable names begin with the `CI_MERGE_REQUEST_` prefix.
are mature, scalable, support [high availability](../../administration/high_availability/README.md)
and are used today on GitLab.com.
It is not necessary to have GitLab installed on Kubernetes in order to use [GitLab Kubernetes integration](https://docs.gitlab.com/ee/user/project/clusters/index.html).
## Introduction
The `gitlab` chart is the best way to operate GitLab on Kubernetes. This chart
contains all the required components to get started, and can scale to large deployments.
-[No in-cluster HA database](https://gitlab.com/charts/gitlab/issues/48)
- MySQL will not be supported, as support is [deprecated within GitLab](https://docs.gitlab.com/omnibus/settings/database.html#using-a-mysql-database-management-server-enterprise-edition-only)
## Installing GitLab using the Helm Chart
The `gitlab` chart includes all required dependencies, and takes a few minutes
to deploy.
TIP: **Tip:**
For production deployments, we strongly recommend using the
1. A [wildcard DNS entry and external IP address](preparation/networking.md)
1.[Authenticate and connect](preparation/connect.md) to the cluster
1. Configure and initialize [Helm Tiller](preparation/tiller.md).
### Deployment of GitLab to Kubernetes
To deploy GitLab, the following three parameters are required:
-`global.hosts.domain`: the [base domain](preparation/networking.md) of the
wildcard host entry. For example, `example.com` if the wild card entry is
`*.example.com`.
-`global.hosts.externalIP`: the [external IP](preparation/networking.md) which
the wildcard DNS resolves to.
-`certmanager-issuer.email`: the email address to use when requesting new SSL
certificates from Let's Encrypt.
NOTE: **Note:**
For deployments to Amazon EKS, there are
[additional configuration requirements](preparation/eks.md). A full list of
configuration options is [also available](https://gitlab.com/charts/gitlab/blob/master/doc/installation/command-line-options.md).
Once you have all of your configuration options collected, you can get any
dependencies and run helm. In this example, the helm release is named "gitlab":
```sh
helm repo add gitlab https://charts.gitlab.io/
helm repo update
helm upgrade --install gitlab gitlab/gitlab \
--timeout 600 \
--set global.hosts.domain=example.com \
--set global.hosts.externalIP=10.10.10.10 \
--set certmanager-issuer.email=email@example.com
```
### Monitoring the Deployment
This will output the list of resources installed once the deployment finishes,
which may take 5-10 minutes.
The status of the deployment can be checked by running `helm status gitlab`
which can also be done while the deployment is taking place if you run the
command in another terminal.
### Initial login
You can access the GitLab instance by visiting the domain name beginning with
`gitlab.` followed by the domain specified during installation. From the example
above, the URL would be `https://gitlab.example.com`.
If you manually created the secret for initial root password, you
can use that to sign in as `root` user. If not, GitLab automatically
created a random password for `root` user. This can be extracted by the
following command (replace `<name>` by name of the release - which is `gitlab`
if you used the command above):
```sh
kubectl get secret <name>-gitlab-initial-root-password -ojsonpath={.data.password} | base64--decode;echo
```
### Outgoing email
By default outgoing email is disabled. To enable it, provide details for your SMTP server
using the `global.smtp` and `global.email` settings. You can find details for these settings in the
[command line options](https://gitlab.com/charts/gitlab/blob/master/doc/installation/command-line-options.md#email-configuration).
If your SMTP server requires authentication make sure to read the section on providing
your password in the [secrets documentation](https://gitlab.com/charts/gitlab/blob/master/doc/installation/secrets.md#smtp-password).
You can disable authentication settings with `--set global.smtp.authentication=""`.
If your Kubernetes cluster is on GKE, be aware that SMTP port [25 is blocked](https://cloud.google.com/compute/docs/tutorials/sending-mail/#using_standard_email_ports).
### Deploying the Community Edition
To deploy the Community Edition, include these options in your `helm install` command:
There are a few nuances to Amazon EKS which are important to be aware of, when deploying GitLab.
## Persistent volume management
There are two methods to manage volume claims on Kubernetes:
1. Manually creating each persistent volume (recommended on EKS)
1. Utilizing dynamic provisioning to automatically create the persistent volumes
### Manual provisioning of volumes (Recommended)
Manually creating the volumes allows you to control the zone of each volume, as well as all other details supported by the underlying storage.
Follow our documentation on [manually creating persistent volumes](https://gitlab.com/charts/gitlab/blob/master/doc/installation/storage.md#manually-creating-static-volumes).
### Dynamic provisioning of volumes
Dynamic provisioning utilizes a Kubernetes provisioner, like `aws-ebs`, to automatically create persistent volumes to fulfill each claim.
With EKS, there are a few important details to keep in mind:
1. Clusters are required to span multiple AZ's
1. Kubernetes volume provisioners create volumes across zones without regard to which pod they belong to. This leads to scenarios where a pod with multiple volumes being unable to start due to the volumes being in different zones.
1. There is no default Storage Class.
The easiest way to solve this and still utilize dynamic provisioning is to utilize, or create, a Storage Class that is locked to a specific zone.
> **Note**: Restricting volumes to specific zone will cause GitLab and any other application using this Storage Class to only reside in that zone. For multiple zone support, utilize [manually provisioned volumes](#manual-provisioning-of-volumes-recommended).
To create the storage class, download and edit Amazon EKS's [sample Storage Class](https://docs.aws.amazon.com/eks/latest/userguide/storage-classes.html) and add the following parameter:
```yaml
parameters:
zone:<desired-zone>
```
Then [specify the Storage Class](https://gitlab.com/charts/gitlab/blob/master/doc/installation/storage.md#using-a-custom-storage-class) name when deploying GitLab.
## External access to GitLab
By default, GitLab will an deploy an ingress which will create an associated Elastic Load Balancer. Since the DNS names of ELB's cannot be known ahead of time, it is difficult to utilize Let's Encrypt to automatically provision HTTPS certificates.
We recommend [using your own certificates](https://gitlab.com/charts/gitlab/blob/master/doc/installation/tls.md#option-2-use-your-own-wildcard-certificate), and then mapping your desired DNS name to the created ELB using a CNAME record.
This document was moved to [another location](https://docs.gitlab.com/charts/installation/cloud/eks.html).
Amazon EKS utilizes Elastic Load Balancers, which are addressed by DNS name and
cannot be known ahead of time. If you're using EKS, you can skip this section.
The `gitlab` chart configures a GitLab server and Kubernetes cluster which can support dynamic [Review Apps](https://docs.gitlab.com/ee/ci/review_apps/index.html), as well as services like the integrated [Container Registry](https://docs.gitlab.com/ee/user/project/container_registry.html).
To support the GitLab services and dynamic environments, a wildcard DNS entry is required which resolves to the external IP.
## External IP
To provision an external IP on GCP and Azure, simply request a new address from the Networking section. Ensure that the region matches the region your container cluster is created in. Note, it is important that the IP is not assigned at this point in time. It will be automatically assigned once the Helm chart is installed, to the Load Balancer.
Set `global.hosts.externalIP` to this IP address when [deploying GitLab](../gitlab_chart.md#installing-gitlab-using-the-helm-chart).
Then, create a [wildcard DNS record](#wildcard-dns-entry) which resolves to this IP address.
### Creating an external IP on GCP
When creating the external IP, it is critical to create it in the same region as your cluster. Otherwise, the IP address will fail to bind to the Load Balancer.
1. Open the [web console](https://console.cloud.google.com)
1. In the sidebar, browse to `VPC Network > External IP addresses`
1. Click `Reserve static address`
1. Choose `Regional` and select the region of your cluster
1. Leave `Attached to` blank, as it will be automatically assigned during deployment
## Wildcard DNS entry
Now that an external IP address has been allocated, ensure that the wildcard DNS entry you would like to use resolves to this IP. Typically this would be an `A record` for `*`, resolving to the external IP above.
Please consult the documentation for your DNS service for more information on creating DNS records:
To make use of Helm, you must have a [Kubernetes][k8s-io] cluster. Ensure you can
access your cluster using `kubectl`.
Helm consists of two parts, the `helm` client and a `tiller` server inside Kubernetes.
NOTE: **Note:**
If you are not able to run Tiller in your cluster, for example on OpenShift, it
is possible to use [Tiller locally](https://docs.gitlab.com/charts/installation/tools.html#local-tiller)
and avoid deploying it into the cluster. This should only be used when Tiller
cannot be normally deployed.
## Initialize Helm and Tiller
Tiller is deployed into the cluster and interacts with the Kubernetes API to deploy your applications. If role based access control (RBAC) is enabled, Tiller will need to be [granted permissions](#preparing-for-helm-with-rbac) to allow it to talk to the Kubernetes API.
If RBAC is not enabled, skip to [initializing Helm](#initialize-helm).
If you are not sure whether RBAC is enabled in your cluster, or to learn more, read through our [RBAC documentation](rbac.md).
## Preparing for Helm with RBAC
Helm's Tiller will need to be granted permissions to perform operations. These instructions grant cluster wide permissions, however for more advanced deployments [permissions can be restricted to a single namespace](https://docs.helm.sh/using_helm/#example-deploy-tiller-in-a-namespace-restricted-to-deploying-resources-only-in-that-namespace). To grant access to the cluster, we will create a new `tiller` service account and bind it to the `cluster-admin` role.
Create a file `rbac-config.yaml` with the following contents:
```yaml
apiVersion:v1
kind:ServiceAccount
metadata:
name:tiller
namespace:kube-system
---
apiVersion:rbac.authorization.k8s.io/v1beta1
kind:ClusterRoleBinding
metadata:
name:tiller
roleRef:
apiGroup:rbac.authorization.k8s.io
kind:ClusterRole
name:cluster-admin
subjects:
-kind:ServiceAccount
name:tiller
namespace:kube-system
```
Next we need to connect to the cluster and upload the RBAC config.
### Upload the RBAC config
Some clusters require authentication to use `kubectl` to create the Tiller roles.
#### Upload the RBAC config as an admin user (GKE)
For GKE, you need to obtain the admin credentials. This command will output the admin password:
In order to work with the GitLab Helm charts, `kubectl` and `helm` must be installed and configured on your computer.
## Installing `kubectl`
`kubectl` is the Kubernetes command line tool, which can be used to deploy settings to the cluster.
Follow the [official documentation](https://kubernetes.io/docs/tasks/tools/install-kubectl/) for the most up to date instructions.
## Installing `helm`
Helm is a package management tool for Kubernetes, and is used to deploy charts.
You can get Helm from the project's [releases page](https://github.com/kubernetes/helm/releases), or follow other options under the official documentation of [Installing Helm](https://docs.helm.sh/using_helm/#installing-helm).
# Next steps
Once installed, proceed to the next [installation step](../gitlab_chart.md#installing-gitlab-using-the-helm-chart).
This document was moved to [another location](https://docs.gitlab.com/charts/installation/tools.html).