debian-mirror-gitlab/doc/user/clusters/agent/install/index.md
2021-12-11 22:18:48 +05:30

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---
stage: Configure
group: Configure
info: To determine the technical writer assigned to the Stage/Group associated with this page, see https://about.gitlab.com/handbook/engineering/ux/technical-writing/#assignments
---
# Install the GitLab Kubernetes Agent **(FREE)**
> [Moved](https://gitlab.com/groups/gitlab-org/-/epics/6290) to GitLab Free in 14.5.
To get started with the GitLab Kubernetes Agent, install it in your cluster.
Pre-requisites:
- An existing Kubernetes cluster.
- An account on GitLab.
## Installation steps
To install the [GitLab Kubernetes Agent](../index.md) in your cluster:
1. [Set up the Kubernetes Agent Server](#set-up-the-kubernetes-agent-server) for your GitLab instance.
1. [Define a configuration repository](#define-a-configuration-repository).
1. [Create an Agent record in GitLab](#create-an-agent-record-in-gitlab).
1. [Install the Agent into the cluster](#install-the-agent-into-the-cluster).
1. [Generate and copy a Secret token used to connect to the Agent](#create-the-kubernetes-secret).
1. [Create manifest files](#create-manifest-files).
<i class="fa fa-youtube-play youtube" aria-hidden="true"></i> Watch a GitLab 14.2 [walking-through video](https://www.youtube.com/watch?v=XuBpKtsgGkE) with this process.
### Set up the Kubernetes Agent Server
> [Introduced](https://gitlab.com/groups/gitlab-org/-/epics/3834) in [GitLab Premium](https://about.gitlab.com/pricing/) 13.10, the GitLab Kubernetes Agent Server (KAS) became available on GitLab.com under `wss://kas.gitlab.com`.
To use the KAS:
- If you are a self-managed user, follow the instructions to [install the Kubernetes Agent Server](../../../../administration/clusters/kas.md).
- If you are a GitLab.com user, when you [set up the configuration repository](#define-a-configuration-repository) for your agent, use `wss://kas.gitlab.com` as the `--kas-address`.
### Define a configuration repository
> - [Introduced](https://gitlab.com/gitlab-org/gitlab/-/issues/259669) in GitLab 13.7, the Agent manifest configuration can be added to multiple directories (or subdirectories) of its repository.
> - Group authorization was [introduced](https://gitlab.com/groups/gitlab-org/-/epics/5784) in GitLab 14.3.
To configure an Agent, you need:
1. A GitLab repository to hold the configuration file.
1. Install the Agent in a cluster.
After installed, when you update the configuration file, GitLab transmits the
information to the cluster automatically without downtime.
In your repository, add the Agent configuration file under:
```plaintext
.gitlab/agents/<agent-name>/config.yaml
```
Make sure that `<agent-name>` conforms to the [Agent's naming format](https://gitlab.com/gitlab-org/cluster-integration/gitlab-agent/-/blob/master/doc/identity_and_auth.md#agent-identity-and-name).
Your `config.yaml` file specifies all configurations of the Agent, such as:
- The manifest projects to synchronize.
- The groups that can access this Agent via the [CI/CD Tunnel](../ci_cd_tunnel.md).
- The address of the `hubble-relay` for the Network Security policy integrations.
As an example, a minimal Agent configuration that sets up only the manifest
synchronizations is:
```yaml
gitops:
manifest_projects:
# The `id` is the path to the Git repository holding your manifest files
- id: "path/to/your-manifest-project-1"
paths:
- glob: '/**/*.{yaml,yml,json}'
```
All the options for the [Kubernetes Agent configuration repository](../repository.md) are documented separately.
### Create an Agent record in GitLab
> [Introduced](https://gitlab.com/groups/gitlab-org/-/epics/5786) in GitLab 14.1, you can create a new Agent record directly from the GitLab UI.
Next, create a GitLab Rails Agent record to associate it with
the configuration repository project. Creating this record also creates a Secret needed to configure
the Agent in subsequent steps.
In GitLab:
1. Ensure that [GitLab CI/CD is enabled in your project](../../../../ci/enable_or_disable_ci.md#enable-cicd-in-a-project).
1. From your project's sidebar, select **Infrastructure > Kubernetes clusters**.
1. Select **Actions**.
1. From the **Select an Agent** dropdown, select the Agent you want to connect and select **Register Agent** to access the installation form.
1. The form reveals your registration token. Securely store this secret token as you cannot view it again.
1. Copy the command under **Recommended installation method**.
In your computer:
1. Open your local terminal and connect to your cluster.
1. Run the command you copied from the installation form.
### Install the Agent into the cluster
To install the in-cluster component of the Agent, first you need to define a namespace. To create a new namespace,
for example, `gitlab-kubernetes-agent`, run:
```shell
kubectl create namespace gitlab-kubernetes-agent
```
To perform a one-liner installation, run the command below. Make sure to replace:
- `your-agent-token` with the token received from the previous step (identified as `secret` in the JSON output).
- `gitlab-kubernetes-agent` with the namespace you defined in the previous step.
- `wss://kas.gitlab.example.com` with the configured access of the Kubernetes Agent Server (KAS). For GitLab.com users, the KAS is available under `wss://kas.gitlab.com`.
- `--agent-version=vX.Y.Z` with the latest released patch version matching your GitLab installation's major and minor versions. For example, for GitLab v13.9.0, use `--agent-version=v13.9.1`. You can find your GitLab version under the "Help/Help" menu.
```shell
docker run --pull=always --rm registry.gitlab.com/gitlab-org/cluster-integration/gitlab-agent/cli:stable generate --agent-token=your-agent-token --kas-address=wss://kas.gitlab.example.com --agent-version=vX.Y.Z --namespace gitlab-kubernetes-agent | kubectl apply -f -
```
WARNING:
`--agent-version stable` can be used to refer to the latest stable release at the time when the command runs. It's fine for
testing purposes but for production please make sure to specify a matching version explicitly.
To find out the various options the above Docker container supports, run:
```shell
docker run --pull=always --rm registry.gitlab.com/gitlab-org/cluster-integration/gitlab-agent/cli:stable generate --help
```
## Advanced installation
For more advanced configurations, we recommend to use [the `kpt` based installation method](https://gitlab.com/gitlab-org/cluster-integration/gitlab-agent/-/tree/master/build/deployment/gitlab-agent).
Otherwise, follow the manual installation steps described below.
### Create the Kubernetes secret
After generating the token, you must apply it to the Kubernetes cluster.
To create your Secret, run:
```shell
kubectl create secret generic -n gitlab-kubernetes-agent gitlab-kubernetes-agent-token --from-literal=token='YOUR_AGENT_TOKEN'
```
The following example file contains the
Kubernetes resources required for the Agent to be installed. You can modify this
example [`resources.yml` file](#example-resourcesyml-file) in the following ways:
- Replace `namespace: gitlab-kubernetes-agent` with `namespace: <YOUR-DESIRED-NAMESPACE>`.
- You can configure `kas-address` (Kubernetes Agent Server) in several ways.
The agent can use the WebSockets or gRPC protocols to connect to the Agent Server.
Select the option appropriate for your cluster configuration and GitLab architecture:
- The `wss` scheme (an encrypted WebSockets connection) is specified by default
after you install the `gitlab-kas` sub-chart, or enable `gitlab-kas` for Omnibus GitLab.
When using the sub-chart, you must set `wss://kas.host.tld:443` as
`kas-address`, where `host.tld` is the domain you've setup for your GitLab installation.
When using Omnibus GitLab, you must set `wss://GitLab.host.tld:443/-/kubernetes-agent/` as
`kas-address`, where `GitLab.host.tld` is your GitLab hostname.
- When using the sub-chart, specify the `ws` scheme (such as `ws://kas.host.tld:80`)
to use an unencrypted WebSockets connection.
When using the Omnibus GitLab, specify the `ws` scheme (such as `ws://GitLab.host.tld:80/-/kubernetes-agent/`).
- Specify the `grpc` scheme if both Agent and Server are installed in one cluster.
In this case, you may specify `kas-address` value as
`grpc://gitlab-kas.<your-namespace>:8150`) to use gRPC directly, where `gitlab-kas`
is the name of the service created by `gitlab-kas` chart, and `<your-namespace>`
is the namespace where the chart was installed.
- Specify the `grpcs` scheme to use an encrypted gRPC connection.
- When deploying KAS through the [GitLab chart](https://docs.gitlab.com/charts/), it's possible to customize the
`kas-address` for `wss` and `ws` schemes to whatever you need.
Check the [chart's KAS Ingress documentation](https://docs.gitlab.com/charts/charts/gitlab/kas/#ingress)
to learn more about it.
- In the near future, Omnibus GitLab intends to provision `gitlab-kas` under a sub-domain by default, instead of the `/-/kubernetes-agent/` path. Please follow [this issue](https://gitlab.com/gitlab-org/omnibus-gitlab/-/issues/5784) for details.
- If you defined your own secret name, replace `gitlab-kubernetes-agent-token` with your
secret name in the `secretName:` section.
To apply this file, run the following command:
```shell
kubectl apply -n gitlab-kubernetes-agent -f ./resources.yml
```
To review your configuration, run the following command:
```shell
$ kubectl get pods -n gitlab-kubernetes-agent
NAMESPACE NAME READY STATUS RESTARTS AGE
gitlab-kubernetes-agent gitlab-kubernetes-agent-77689f7dcb-5skqk 1/1 Running 0 51s
```
#### Example `resources.yml` file
```yaml
---
apiVersion: v1
kind: Namespace
metadata:
name: gitlab-kubernetes-agent
---
apiVersion: v1
kind: ServiceAccount
metadata:
name: gitlab-kubernetes-agent
---
apiVersion: apps/v1
kind: Deployment
metadata:
name: gitlab-kubernetes-agent
spec:
replicas: 1
selector:
matchLabels:
app: gitlab-kubernetes-agent
template:
metadata:
labels:
app: gitlab-kubernetes-agent
spec:
serviceAccountName: gitlab-kubernetes-agent
containers:
- name: agent
# Make sure to specify a matching version for production
image: "registry.gitlab.com/gitlab-org/cluster-integration/gitlab-agent/agentk:vX.Y.Z"
args:
- --token-file=/config/token
- --kas-address
- wss://kas.host.tld:443 # replace this line with the line below if using Omnibus GitLab or GitLab.com.
# - wss://gitlab.host.tld:443/-/kubernetes-agent/
# - wss://kas.gitlab.com # for GitLab.com users, use this KAS.
# - grpc://host.docker.internal:8150 # use this attribute when connecting from Docker.
volumeMounts:
- name: token-volume
mountPath: /config
volumes:
- name: token-volume
secret:
secretName: gitlab-kubernetes-agent-token
strategy:
type: RollingUpdate
rollingUpdate:
maxSurge: 0
maxUnavailable: 1
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRole
metadata:
name: gitlab-kubernetes-agent-write
rules:
- resources:
- '*'
apiGroups:
- '*'
verbs:
- create
- update
- delete
- patch
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
name: gitlab-kubernetes-agent-write-binding
roleRef:
name: gitlab-kubernetes-agent-write
kind: ClusterRole
apiGroup: rbac.authorization.k8s.io
subjects:
- name: gitlab-kubernetes-agent
kind: ServiceAccount
namespace: gitlab-kubernetes-agent
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRole
metadata:
name: gitlab-kubernetes-agent-read
rules:
- resources:
- '*'
apiGroups:
- '*'
verbs:
- get
- list
- watch
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
name: gitlab-kubernetes-agent-read-binding
roleRef:
name: gitlab-kubernetes-agent-read
kind: ClusterRole
apiGroup: rbac.authorization.k8s.io
subjects:
- name: gitlab-kubernetes-agent
kind: ServiceAccount
namespace: gitlab-kubernetes-agent
```
### Create manifest files
In a previous step, you configured a `config.yaml` to point to the GitLab projects
the Agent should synchronize. Agent monitors each of those projects for changes to the manifest files it contains. You can auto-generate manifest files with a
templating engine or other means.
The agent is authorized to download manifests for the configuration
project, and public projects. Support for other private projects is
planned in the issue [Agent authorization for private manifest
projects](https://gitlab.com/gitlab-org/gitlab/-/issues/220912).
Each time you push a change to a monitored manifest repository, the Agent logs the change:
```plaintext
2020-09-15_14:09:04.87946 gitlab-k8s-agent : time="2020-09-15T10:09:04-04:00" level=info msg="Config: new commit" agent_id=1 commit_id=e6a3651f1faa2e928fe6120e254c122451be4eea
```
#### Example manifest file
This file creates a minimal `ConfigMap`:
```yaml
apiVersion: v1
kind: ConfigMap
metadata:
name: demo-map
namespace: gitlab-kubernetes-agent # Can be any namespace managed by you that the agent has access to.
data:
key: value
```
## Example projects
The following example projects can help you get started with the Kubernetes Agent.
- [Configuration repository](https://gitlab.com/gitlab-org/configure/examples/kubernetes-agent)
- This basic GitOps example deploys NGINX: [Manifest repository](https://gitlab.com/gitlab-org/configure/examples/gitops-project)
## View installed Agents
Users with at least the [Developer](../../../permissions.md) can access the user interface
for the GitLab Kubernetes Agent at **Infrastructure > Kubernetes clusters**, under the
**Agent** tab. This page lists all registered agents for the current project,
and the configuration directory for each agent:
![GitLab Kubernetes Agent list UI](../../img/kubernetes-agent-ui-list_v14_5.png)
Additional management interfaces are planned for the GitLab Kubernetes Agent.
[Provide more feedback in the related epic](https://gitlab.com/groups/gitlab-org/-/epics/4739).
## Upgrades and version compatibility
The GitLab Kubernetes Agent is comprised of two major components: `agentk` and `kas`.
As we provide `kas` installers built into the various GitLab installation methods, the required `kas` version corresponds to the GitLab `major.minor` (X.Y) versions.
At the same time, `agentk` and `kas` can differ by 1 minor version in either direction. For example,
`agentk` 14.4 supports `kas` 14.3, 14.4, and 14.5 (regardless of the patch).
A feature introduced in a given GitLab minor version might work with other `agentk` or `kas` versions.
To make sure that it works, use at least the same `agentk` and `kas` minor version. For example,
if your GitLab version is 14.2, use at least `agentk` 14.2 and `kas` 14.2.
We recommend upgrading your `kas` installations together with GitLab instances' upgrades, and to upgrade the `agentk` installations after upgrading GitLab.
The available `agentk` and `kas` versions can be found in
[the container registry](https://gitlab.com/gitlab-org/cluster-integration/gitlab-agent/container_registry/).