Chapter 1. Setting up an Argo CD instance
By default, Red Hat OpenShift GitOps installs an instance of Argo CD in the openshift-gitops
namespace with additional permissions for managing certain cluster-scoped resources. This default Argo CD instance is also called as the default cluster-scoped instance.
For GitOps version 1.13 and later, the route TLS termination is set as default to the reencrypt
mode for both the default and user-defined Argo CD instances. TLS connections to the Argo CD instances now receive the default ingress certificate that is set in OpenShift Container Platform, instead of the self-signed Argo CD certificate.
You can modify the route TLS termination policy by configuring the .spec.server.route.tls
field of the Argo CD CR.
To manage cluster configurations or deploy applications, you can install and deploy a new user-defined Argo CD instance. By default, any new user-defined instance has permissions to manage resources only in the namespace where it is deployed.
1.1. Installing a user-defined Argo CD instance
To manage cluster configurations or deploy applications, you can install and deploy a new user-defined Argo CD instance.
Prerequisites
-
You have access to the cluster with
cluster-admin
privileges. - You have installed the Red Hat OpenShift GitOps Operator in your cluster.
Procedure
- Log in to the OpenShift Container Platform web console.
-
In the Administrator perspective of the web console, click Operators
Installed Operators. - Create or select the project where you want to install the user-defined Argo CD instance from the Project list.
- Select Red Hat OpenShift GitOps from the installed Operators list and click the Argo CD tab.
Click Create ArgoCD to configure the parameters:
-
Enter the Name of the instance. By default, the Name is set to
example
. Create an external OS Route to access Argo CD server. Click Server
Route and check Enabled. TipYou can alternatively configure YAML to create an external OS Route as shown in the following example:
Example Argo CD with external OS route created
apiVersion: argoproj.io/v1beta1 kind: ArgoCD metadata: name: example namespace: openshift-gitops spec: server: route: enabled: true
-
Optional: Modify the route TLS termination policy by configuring the
.spec.server.route.tls
field of the Argo CD CR.
-
Enter the Name of the instance. By default, the Name is set to
- Click Create.
-
Go to Networking
Routes <instance_name>-server in the project where the user-defined Argo CD instance is installed. -
On the Details tab, click the Argo CD web UI link under Route details
Location. The Argo CD web UI opens in a separate browser window. Optional: To log in with your OpenShift Container Platform credentials, ensure you are a user of the
cluster-admins
group and then select theLOG IN VIA OPENSHIFT
option in the Argo CD user interface.NoteTo be a user of the
cluster-admins
group, use theoc adm groups new cluster-admins <user>
command, where<user>
is the default cluster role that you can bind to users and groups cluster-wide or locally.Obtain the password for the user-defined Argo CD instance:
-
Use the navigation panel to go to the Workloads
Secrets page. - Use the Project list and select the namespace where the user-defined Argo CD instance is created.
- Select the <argo_CD_instance_name>-cluster instance to display the password.
-
On the Details tab, copy the password under Data
admin.password.
-
Use the navigation panel to go to the Workloads
-
Use
admin
as the Username and the copied password as the Password to log in to the Argo CD UI in the new window.
1.2. Configuring common cluster roles by specifying user-defined cluster roles for namespace-scoped instances
As a cluster administrator, when you give an Argo CD access to a namespace by using the argocd.argoproj.io/managed-by
label, the Argo CD assumes namespace-admin
privileges. The Red Hat OpenShift GitOps Operator then automatically creates role bindings for all managed namespaces of the following GitOps control plane components:
- Argo CD Application Controller
- Argo CD server
- Argo CD ApplicationSet Controller
When you provide namespaces to non-administrator users, for example, development teams, they can use the namespace-admin
privileges to modify objects such as network policies. Installing an Argo CD instance in these namespaces gives the development teams admin
privileges and indirectly elevates their assigned privileges. These roles are highly privileged and can delete all resources. As a preventive action, you can define a specific set of reduced permissions to meet your security requirements by configuring common cluster roles for all managed namespaces in the role bindings that the Operator creates for the Argo CD Application Controller and Argo CD server components.
To configure common cluster roles for all managed namespaces, you can specify user-defined cluster roles for the CONTROLLER_CLUSTER_ROLE
and SERVER_CLUSTER_ROLE
environment variables in the Operator’s Subscription
object YAML file. As a result, instead of creating the default admin
role, the Operator uses the existing user-defined cluster roles and creates role bindings for all managed namespaces.
Prerequisites
- You have logged in to the OpenShift Container Platform cluster as an administrator.
- You have installed the Red Hat OpenShift GitOps Operator on your OpenShift Container Platform cluster.
Procedure
-
In the Administrator perspective, navigate to Administration
CustomResourceDefinitions. - Find the Subscription CRD and click to open it.
- Select the Instances tab and click the openshift-gitops-operator subscription.
Select the YAML tab and make your customization:
Specify the user-defined cluster roles for the
CONTROLLER_CLUSTER_ROLE
andSERVER_CLUSTER_ROLE
environment variables:Example Subscription
apiVersion: operators.coreos.com/v1alpha1 kind: Subscription metadata: name: openshift-gitops-operator namespace: openshift-gitops-operator spec: config: env: - name: CONTROLLER_CLUSTER_ROLE value: gitops-controller-role 1 - name: SERVER_CLUSTER_ROLE value: gitops-server-role 2
Alternatively, you can inject the preceding environment variables directly into the Operator’s Deployment
object YAML file.
1.3. Enabling replicas for Argo CD server and repo server
Argo CD-server and Argo CD-repo-server workloads are stateless. To better distribute your workloads among pods, you can increase the number of Argo CD-server and Argo CD-repo-server replicas. However, if a horizontal autoscaler is enabled on the Argo CD-server, it overrides the number of replicas you set.
Procedure
Set the
replicas
parameters for therepo
andserver
spec to the number of replicas you want to run:Example Argo CD custom resource
apiVersion: argoproj.io/v1beta1 kind: ArgoCD metadata: name: example-argocd labels: example: repo spec: repo: replicas: <number_of_replicas> server: replicas: <number_of_replicas> route: enabled: true path: / tls: insecureEdgeTerminationPolicy: Redirect termination: passthrough wildcardPolicy: None
1.4. Deploying resources to a different namespace
To allow Argo CD to manage resources in other namespaces apart from where it is installed, configure the target namespace with a argocd.argoproj.io/managed-by
label.
Procedure
Configure the namespace:
$ oc label namespace <namespace> \ argocd.argoproj.io/managed-by=<namespace> 1
- 1
- The namespace where Argo CD is installed.
1.5. Customizing the Argo CD console link
In a multi-tenant cluster, users might have to deal with multiple instances of Argo CD. For example, after installing an Argo CD instance in your namespace, you might find a different Argo CD instance attached to the Argo CD console link, instead of your own Argo CD instance, in the Console Application Launcher.
You can customize the Argo CD console link by setting the DISABLE_DEFAULT_ARGOCD_CONSOLELINK
environment variable:
-
When you set
DISABLE_DEFAULT_ARGOCD_CONSOLELINK
totrue
, the Argo CD console link is permanently deleted. -
When you set
DISABLE_DEFAULT_ARGOCD_CONSOLELINK
tofalse
or use the default value, the Argo CD console link is temporarily deleted and visible again when the Argo CD route is reconciled.
Prerequisites
- You have logged in to the OpenShift Container Platform cluster as an administrator.
- You have installed the Red Hat OpenShift GitOps Operator.
Procedure
-
In the Administrator perspective, navigate to Administration
CustomResourceDefinitions. - Find the Subscription CRD and click to open it.
- Select the Instances tab and click the openshift-gitops-operator subscription.
Select the YAML tab and make your customization:
To enable or disable the Argo CD console link, edit the value of
DISABLE_DEFAULT_ARGOCD_CONSOLELINK
as needed:apiVersion: operators.coreos.com/v1alpha1 kind: Subscription metadata: name: openshift-gitops-operator spec: config: env: - name: DISABLE_DEFAULT_ARGOCD_CONSOLELINK value: 'true'