Flux Vs Argo CD| Which is best|Similarities vs Differences

#flux  #argocd #argo #gitops #sre #devops #similarities #differences #git
Flux

Flux uses Kustomize heavily. Its Kustomize Controller renders and applies all the manifests that Flux syncs from the source repository, even when using raw Kubernetes YAML. Flux will create a kustomization.yaml file on the fly if Kustomize wasn’t detected. You can use DependsOn to create dependencies between Kustomizations.

Flux also has native support for Helm. Its Helm Controller manages all the Helm charts you want to deploy onto the cluster. Flux uses the native Helm golang library to deploy a Helm release onto the cluster. You also get the advantage of Helm’s chart hooks for ordering. If you are using a hub/spoke model (more on multicluster later), you can also see Helm charts installed on other clusters. Similar to the Kustomize controller, you can use DependsOn to create dependencies.

Argo CD

Argo CD also supports Kustomize and raw Kubernetes YAML. It can, however, apply raw YAML files directly, without using Kustomize. This can have side effects of Argo CD applications not syncing right away as resources need to be reapplied in a retry, or use ordering built into Argo CD.

Argo CD does the equivalent of kubectl apply -f or a kubectl apply -k if Kustomize is detected. This is by design, as the Argo CD creators wanted to emulate the kubectl client as closely as possible. You also have more control over ordering of individual resources (i.e. specific YAML file) with syncwaves and phases. This allows you to apply each YAML manifest one at a time.

Argo CD also has support for Helm, but approaches it in a different way. Argo CD does not use the Helm golang library directly but instead uses Helm to render the template files and pipes them directly to kubectl. Helm chart hooks are converted into Argo CD syncwaves/hooks (more on this next) where it can. This has the side effect of users not being able to use the Helm command-line interface (CLI) against the cluster because Helm install wasn’t called in the first place (i.e. helm ls will return empty).

Web UI
A web user interface doesn’t change the functionality of either tool, but it’s worth noticing the differences. Both tools have a feature-rich CLI that doesn’t impede on functionality.

Flux

Flux, by itself, does not have a web UI. There is an experimental UI  started about a year ago, but nothing official. There are open source platforms like Weave GitOps Core that are based on Flux that have a UI.

Argo CD

Argo CD has a rich UI and was built with the UI in mind, so it’s been there from the beginning. It also integrates with Argo CD’s access control policies (more on that next) and has the ability to show a “read-only” dashboard.