From 70897cebfefab56a80561bb383eca4cab8d3408a Mon Sep 17 00:00:00 2001 From: Daniel Holbach Date: Tue, 4 Aug 2020 16:10:17 +0200 Subject: [PATCH] Add initial set of FAQ closes: #142 --- docs/faq/index.md | 93 +++++++++++++++++++++++++++++++++++++++++++++++ mkdocs.yml | 1 + 2 files changed, 94 insertions(+) create mode 100644 docs/faq/index.md diff --git a/docs/faq/index.md b/docs/faq/index.md new file mode 100644 index 00000000..befad671 --- /dev/null +++ b/docs/faq/index.md @@ -0,0 +1,93 @@ +# Frequently asked questions + +## General questions + +### What does the GitOps Toolkit mean for Flux? + +Flux v1 is a monolithic do-it-all operator; the GitOps Toolkit separates the functionalities into specialized controllers. + +Flux v2 will be a curated configuration of the GitOps Toolkit, which you can install and operate simply using the `tk` command. You can easily pick and choose the functionality you need and extend it to serve your own purposes. + +The timeline we are looking at right now is: + +1. Put Flux v1 into maintenance mode (no new features being added; bugfixes and CVEs patched only). +1. Continue work on [GitOps Toolkit roadmap](https://toolkit.fluxcd.io/roadmap/). +1. We will provide transition guides for specific user groups, e.g. users of Flux v1 in read-only mode, or of Helm Operator v1, etc. once the functionality is integrated in the GitOps Toolkit and it's deemed "ready". +1. Once the use-cases of Flux v1 are covered, we will continue supporting Flux v1 for 6 months. This will be the transition period before it's considered unsupported. + +### Why did you rewrite Flux? + +The GitOps Toolkit implements its functionality in individual controllers, which allowed us to address long-standing feature requests much more easily. + +By basing these controllers on modern Kubernetes tooling (`controller-runtime` libraries), they can be dynamically configured with Kubernetes custom resources either by cluster admins or by other automated tools -- and you get greatly increased observability. + +This gave us the opportunity to build the GitOps Toolkit with the top Flux feature requests in mind: + +- Supporting multiple source Git repositories +- Operational insight through health checks, events and alerts +- Multi-tenancy capabilities, like applying each source repository with its own set of permissions + +On top of that, testing the GitOps Toolkit and understanding the codebase becomes a lot easier. + +### What are significant new differences between Flux v1 and the GitOps Toolkit? + +#### Reconciliation + +Flux v1 | Toolkit component driven "Flux v2" +---------------------------------- | ---------------------------------- +Limited to a single Git repository | Multiple Git repositories +Declarative config via arguments in the Flux deployment | `GitRepository` custom resource, which produces an artifact which can be reconciled by other controllers +Follow `HEAD` of Git branches | Supports Git branches, pinning on commits and tags, follow SemVer tag ranges +Suspending of reconciliation by downscaling Flux deployment | Reconciliation can be paused per resource by suspending the `GitRepository` +Credentials config via Arguments and/or Secret volume mounts in the Flux pod | Credentials config per `GitRepository` resource: SSH private key, HTTP/S username/password/token, OpenPGP public keys + +#### `kustomize` support + +Flux v1 | Toolkit component driven "Flux v2" +---------------------------------- | ---------------------------------- +Declarative config through `.flux.yaml` files in the Git repository | Declarative config through a `Kustomization` custom resource, consuming the artifact from the GitRepository +Manifests are generated via shell exec and then reconciled by `fluxd` | Generation, server-side validation, and reconciliation is handled by a specialised `kustomize-controller` +Reconciliation using the service account of the Flux deployment | Support for service account impersonation +Garbage collection needs cluster role binding for Flux to query the Kubernetes discovery API | Garbage collection needs no cluster role binding or access to Kubernetes discovery API +Support for custom commands and generators executed by fluxd in a POSIX shell | No support for custom commands + +#### Helm integration + +Flux v1 | Toolkit component driven "Flux v2" +---------------------------------- | ---------------------------------- +Declarative config in a single Helm custom resource | Declarative config through `HelmRepository`, `HelmChart` and `HelmRelease` custom resources +Chart synchronisation embedded in the operator | Extensive release configuration options, and a reconciliation interval per source +Support for fixed SemVer versions from Helm repositories | Support for SemVer ranges for `HelmChart` resources +Git repository synchronisation on a global interval | Planned support for charts from GitRepository sources +Limited observability via the status object of the HelmRelease resource | Better observability via the HelmRelease status object, Kubernetes events, and notifications +Resource heavy, relatively slow | Better performance + +#### Notifications, webhooks, observability + +Flux v1 | Toolkit component driven "Flux v2" +---------------------------------- | ---------------------------------- +Emits "custom Flux events" to a webhook endpoint | Emits Kubernetes events for all custom resources part of the Toolkit +RPC endpoint can be configured to a 3rd party solution like FluxCloud to be forwarded as notifications to e.g. Slack | Toolkit components can be configured to POST the events to a `notification-controller` endpoint. Selective forwarding of POSTed events as notifications using `Provider` and `Alert` custom resources. +Webhook receiver is a side-project | Webhook receiver, handling a wide range of platforms, is included +Unstructured logging | Structured logging for all components +Custom Prometheus metrics | Generic / common `controller-runtime` Prometheus metrics + +### How can I get involved? + +There are a variety of ways and we look forward to having you on board building the future of GitOps together: + +- [Discuss the direction](https://github.com/fluxcd/toolkit/discussions) of the GitOps Toolkit with us +- Join us in #flux-dev on the [CNCF Slack](https://slack.cncf.io) +- Check out our [contributor docs](https://toolkit.fluxcd.io/contributing/) +- Take a look at the [roadmap of the GitOps Toolkit](https://toolkit.fluxcd.io/roadmap/) + +### Are there any breaking changes? + +- In Flux v1 Kustomize support was implemented through `.flux.yaml` files in the Git repository. As indicated in the comparison table above, while this approach worked, we found it to be error-prone and hard to debug. The new [Kustomization CR](https://github.com/fluxcd/kustomize-controller/blob/master/docs/spec/v1alpha1/kustomization.md) should make troubleshooting much easier. Unfortunately we needed to drop the support for custom commands as running arbitrary shell scripts in-cluster poses serious security concerns. +- Helm users: we redesigned the `HelmRelease` API and the automation will work quite differently, so upgrading to `HelmRelease` v2 will require a little work from you, but you will gain more flexibility, better observability and performance. + +### Is the GitOps Toolkit related to the GitOps Engine? + +In an announcement in August 2019, the expectation was set that the Flux project would integrate the GitOps Engine, then being factored out of ArgoCD. Since the result would be backward-incompatible, it would require a major version bump: Flux v2. + +After experimentation and considerable thought, we (the maintainers) have found a path to Flux v2 that we think better serves our vision of GitOps: the GitOps Toolkit. In consequence, we do not now plan to integrate GitOps Engine into Flux. diff --git a/mkdocs.yml b/mkdocs.yml index 01ab799f..11bc77e4 100644 --- a/mkdocs.yml +++ b/mkdocs.yml @@ -120,3 +120,4 @@ nav: - Contributing: contributing/index.md - Dev Guides: - Watching for source changes: dev-guides/source-watcher.md + - FAQ: faq/index.md