ArgoCD#

Intended audience

sysadm staff members

The CD is run by ArgoCD on argocd.softwareheritage.org.

The repositories#

To manage the kubernetes clusters and ArgoCD, 2 git repositories are used:

  • k8s-clusters-conf: Kubernetes yaml files deployed on the clusters, it contains the configurations to apply directly on the clusters. The ArgoCD configuration is also committed in this repository.

  • k8s-private data: private repository with the yaml files to configure the secrets per cluster

Except during the bootstrap phase, the configuration files are automatically applied on the clusters by ArgoCD.

2 others deployment services related are indirectly related to deployments:

  • swh-apps: Image definitions (version and dependencies, docker images definitions)

  • swh-charts: Application definitions, mostly helm charts defining the way to deploy an application. The public configurations per environment are also in this repository due to argocd constraints. The deployment of these applications is done by ArgoCD.

Bootstrap ArgoCD#

Prerequisite: A working kubernetes cluster sized to your needs. At SoftwareHeritage, we chose to deploy a small cluster of 2 nodes which looks enough for our dozen of applications.

Install ArgoCD#

TODO: Detail how it was done in the swh environment

Some working notes are available in a Readme.md in the k8s-clusters-conf repository. It’s based on the official ArgoCD documentation

Upgrade ArgoCD#

Follow the official ArgoCD document procedure

Bootstrap the self configuration management#

ArgoCD is able to manage its own configuration.

To do so, some manual installation steps are needed:

  • Clone the k8s-private-data and k8s-clusters-conf repositories locally (or directly the sysadm-environment repository)

  • Configure the k8s-private-data repository credentials in ArgoCD:

cd k8s-private-data/argocd/repositories
kubectl apply -f k8s-swh-private-data.yaml

  • Declare the ArgoCD that will import all the ArgoCD configuration

cd k8s-clusters-conf/argocd/applications
kubectl apply -f argocd-applications.yaml

After that, ArgoCD will populate itself with all the applications in charge of the clusters configuration and service deployments.

Manage a new kubernetes cluster#

As we saw, ArgoCD can take care of automatically applying and synchronizing the cluster configurations and secrets based on what is committed in the k8s-clusters-conf and k8s-private-data repositories.

A couple of steps are needed to add a new cluster and its associated management applications:

  • Declare the cluster in k8s-private-data/argocd/clusters

    • Copy an existing cluster file and adapt to use the new cluster credentials

  • If this cluster has some secrets, create a directory matching the cluster name at the root of the k8s-private-data repository too

    • Put the secret configurations in the directory in kubernetes yaml files.

Warning

Only the secrets and private data must be put in this repository

  • In the k8s-clusters-conf repository, create a new application in the argocd/applications/cluster-secrets named <cluster-name>.yaml to manage the new cluster secrets under argocd/applications

    Check other applications in this directory and adapt the following properties:

    • metadata.name: change to <cluster-name>-secrets

    • spec.source.path: change to <cluster-name>, it must match the directory created in the k8s-private-data repository

    • spec.destination.server: change to the server url, it must match the stringData.server value in the cluster configuration created in k8s-private-data/argocd/clusters/<cluster-name>.yaml

  • Create a new directory k8s-clusters-conf/<cluster-name> and add the yaml for the static configurations of the cluster (namespace, crd, …)

  • Create a new directory argocd/<cluster-name>

  • Create a new configuration-application.yaml to manage the static configurations

    Copy another configuration application and adapt the following properties:

    • metadata.name: Change to <cluster-name>-configuration

    • spec.source.path: Change to <cluster-name>, it must match the directory name created earlier

    • spec.destination.server: Change to the url of the server as declared in the cluster configuration created in k8s-private-data

Commit and push, ArgoCD will apply all the configurations and will keep it in sync.

Deploy a new service#

The deployments of the services with kubernetes are also managed by ArgoCD.

To create a new application:

  • Identify the cluster on which the service will be deployed

  • Declare a new ArgoCD application in k8s-clusters-conf/argocd/application/<cluster-name>/<application>-application.yaml

Warning

When possible, we try to use helm charts to deploy service.

You can find some other applications used to deploy helm based services in the repository.

More information about the application configuration can also be found in the official ArgoCD documentation

Manage users#

This documentation is based on the official user management documentation (archived link)

Prerequisite#

The argocd cli will be necessary to perform some action relative to the user management.

Add a user#

  • Add the user on the argo-cm.yaml file

  • Add the user role on the argocd-rbac-cm.yaml file If no role is specified, the user will only have a read-only access

g, <user>, role:admin

  • Commit and push your changes, wait a couple of minutes to let ArgoCD apply the changes

  • Modify the user password with the cli

$ # Check the user is created
$ argocd --grpc-web account list
NAME      ENABLED  CAPABILITIES
admin     true     login
newuser   true     apiKey, login
$ # update its password
$ argocd --grpc-web account update-password --account newuser
*** Enter password of currently logged in user (admin):
*** Enter new password for user newuser: XXX
*** Confirm new password for user newuser: XXX
Password updated

Disable a user#

accounts.usertodisable.enabled: "false"

  • Commit and push your change, wait a couple of minutes to let ArgoCD apply the changes

  • Ensure the user is disabled

$ argocd --grpc-web account list
NAME           ENABLED  CAPABILITIES
admin          true     login
usertodisable  false    apiKey, login

Delete a user#

  • Remove the changes committed in the Add a user procedure

  • Commit and push your changes, wait a couple of minutes to let ArgoCD apply the changes

  • Ensure the user is deleted

$ argocd --grpc-web account list
NAME           ENABLED  CAPABILITIES
admin          true     login