Change all references to master branch in docs to main branch

Author: Cecile Robert-Michon

CONTRIBUTING.md

@@ -64,7 +64,7 @@ The documentation is published in form of a book at:
 - [Stable release](https://cluster-api.sigs.k8s.io)
 - [Tip of the main branch](https://tip.cluster-api.sigs.k8s.io/)
 
-The source for the book is [this folder](https://github.com/kubernetes-sigs/cluster-api/tree/master/docs/book/src)
+The source for the book is [this folder](https://github.com/kubernetes-sigs/cluster-api/tree/main/docs/book/src)
 containing markdown files and we use [mdBook][] to build it into a static
 website.
 
@@ -104,7 +104,7 @@ Cluster API uses [GitHub milestones](https://github.com/kubernetes-sigs/cluster-
 
 The Cluster API Enhacement Proposal is the process this project uses to adopt new features, changes to the APIs, changes to contracts between components, or changes to CLI interfaces.
 
-The [template](https://github.com/kubernetes-sigs/cluster-api/blob/master/docs/proposals/YYYYMMDD-template.md), and accepted proposals live under [docs/proposals](https://github.com/kubernetes-sigs/cluster-api/tree/master/docs/proposals).
+The [template](https://github.com/kubernetes-sigs/cluster-api/blob/main/docs/proposals/YYYYMMDD-template.md), and accepted proposals live under [docs/proposals](https://github.com/kubernetes-sigs/cluster-api/tree/main/docs/proposals).
 
 - Proposals or requests for enhacements (RFEs) MUST be associated with an issue.
   - Issues can be placed on the roadmap during planning if there is one or more folks
@@ -229,10 +229,10 @@ Proof of concepts, code experiments, or other initiatives can live under the `ex
 
 ## Breaking Changes
 
-Breaking changes are generally allowed in the `master` branch, as this is the branch used to develop the next minor
+Breaking changes are generally allowed in the `main` branch, as this is the branch used to develop the next minor
 release of Cluster API.
 
-There may be times, however, when `master` is closed for breaking changes. This is likely to happen as we near the
+There may be times, however, when `main` is closed for breaking changes. This is likely to happen as we near the
 release of a new minor version.
 
 Breaking changes are not allowed in release branches, as these represent minor versions that have already been released.

REVIEWING.md

@@ -120,7 +120,7 @@ This makes any change that can impact the Cluster API contract critical and usua
 ### Logging
 
 - For CAPI controllers see [Kubernetes logging conventions](https://git.k8s.io/community/contributors/devel/sig-instrumentation/logging.md).
-- For clusterctl see [clusterctl logging conventions](https://github.com/kubernetes-sigs/cluster-api/blob/master/cmd/clusterctl/log/doc.go).
+- For clusterctl see [clusterctl logging conventions](https://github.com/kubernetes-sigs/cluster-api/blob/main/cmd/clusterctl/log/doc.go).
 
 ### Testing
 

VERSIONING.md

@@ -5,7 +5,7 @@
 - We follow [Semantic Versioning (semver)](https://semver.org/).
 - Cluster API release cadence is Kubernetes Release + 6 weeks.
 - The cadence is subject to change if necessary, refer to the [Milestones](https://github.com/kubernetes-sigs/cluster-api/milestones) page for up-to-date information.
-- The _master_ branch is where development happens, this might include breaking changes.
+- The _main_ branch is where development happens, this might include breaking changes.
 - The _release-X_ branches contain stable, backward compatible code. A new _release-X_ branch is created at every major (X) release.
 
 ## Overview
@@ -36,11 +36,11 @@ that we follow.
 
 ## Branches
 
-Cluster API contains two types of branches: the *master* branch and
+Cluster API contains two types of branches: the *main* branch and
 *release-X* branches.
 
-The *master* branch is where development happens.  All the latest and
-greatest code, including breaking changes, happens on master.
+The *main* branch is where development happens.  All the latest and
+greatest code, including breaking changes, happens on main.
 
 The *release-X* branches contain stable, backwards compatible code.  Every
 major (X) release, a new such branch is created.  It is from these
@@ -109,11 +109,11 @@ Refer to the [releasing document](./docs/developer/releasing.md) for the exact s
 
 Try to avoid breaking changes.  They make life difficult for users, who
 have to rewrite their code when they eventually upgrade, and for
-maintainers/contributors, who have to deal with differences between master
+maintainers/contributors, who have to deal with differences between main
 and stable branches.
 
 That being said, we'll occasionally want to make breaking changes. They'll
-be merged onto master, and will then trigger a major release (see [Release
+be merged onto main, and will then trigger a major release (see [Release
 Process](#release-process)).  Because breaking changes induce a major
 revision, the maintainers may delay a particular breaking change until
 a later date when they are ready to make a major revision with a few
@@ -145,7 +145,7 @@ Development branches:
   changes (we still have to merge/manage multiple branches for development
   and stable)
 
-- can be confusing to contributors, who often expect master to have the
+- can be confusing to contributors, who often expect main to have the
   latest changes.
 
 ### Never break compatibility

docs/book/src/clusterctl/commands/config-cluster.md

@@ -84,7 +84,7 @@ Use the `--from` flag to read cluster templates stored in a GitHub repository or
 
 ```
 clusterctl config cluster my-cluster --kubernetes-version v1.16.3 \
-   --from https://github.com/my-org/my-repository/blob/master/my-template.yaml > my-cluster.yaml
+   --from https://github.com/my-org/my-repository/blob/main/my-template.yaml > my-cluster.yaml
 ```
 
 or

docs/book/src/clusterctl/commands/generate-cluster.md

@@ -75,7 +75,7 @@ Use the `--from` flag to read cluster templates stored in a GitHub repository or
 
 ```
 clusterctl generate cluster my-cluster --kubernetes-version v1.16.3 \
-   --from https://github.com/my-org/my-repository/blob/master/my-template.yaml > my-cluster.yaml
+   --from https://github.com/my-org/my-repository/blob/main/my-template.yaml > my-cluster.yaml
 ```
 
 or

docs/book/src/clusterctl/commands/generate-yaml.md

@@ -21,7 +21,7 @@ Current usage of the command is as follows:
 ```bash
 # Generates a configuration file with variable values using a template from a
 # specific URL.
-clusterctl generate yaml --from https://github.com/foo-org/foo-repository/blob/master/cluster-template.yaml
+clusterctl generate yaml --from https://github.com/foo-org/foo-repository/blob/main/cluster-template.yaml
 
 # Generates a configuration file with variable values using
 # a template stored locally.

docs/book/src/developer/architecture/controllers/bootstrap.md

@@ -5,12 +5,12 @@ Bootstrapping is the process in which:
 1. A cluster is bootstrapped
 1. A machine is bootstrapped and takes on a role within a cluster
 
-[CABPK](https://github.com/kubernetes-sigs/cluster-api/tree/master/bootstrap/kubeadm) is the reference bootstrap provider and is based on `kubeadm`. CABPK codifies the steps for [creating a cluster](https://kubernetes.io/docs/setup/production-environment/tools/kubeadm/create-cluster-kubeadm/) in multiple configurations.
+[CABPK](https://github.com/kubernetes-sigs/cluster-api/tree/main/bootstrap/kubeadm) is the reference bootstrap provider and is based on `kubeadm`. CABPK codifies the steps for [creating a cluster](https://kubernetes.io/docs/setup/production-environment/tools/kubeadm/create-cluster-kubeadm/) in multiple configurations.
 
 ![](../../../images/bootstrap-controller.png)
 
-See [proposal](https://github.com/kubernetes-sigs/cluster-api/blob/master/docs/proposals/20190610-machine-states-preboot-bootstrapping.md) for the full details on how the bootstrap process works.
+See [proposal](https://github.com/kubernetes-sigs/cluster-api/blob/main/docs/proposals/20190610-machine-states-preboot-bootstrapping.md) for the full details on how the bootstrap process works.
 
 ### Implementations
 
-* [Kubeadm](https://github.com/kubernetes-sigs/cluster-api/tree/master/bootstrap/kubeadm) (Reference Implementation)
+* [Kubeadm](https://github.com/kubernetes-sigs/cluster-api/tree/main/bootstrap/kubeadm) (Reference Implementation)

docs/book/src/developer/e2e.md

@@ -204,14 +204,14 @@ test specs for the most common Cluster API use cases.
 [deprecated E2E config file]: https://pkg.go.dev/sigs.k8s.io/cluster-api/test/framework?tab=doc#Config
 [deprecated InitManagementCluster method]: https://pkg.go.dev/sigs.k8s.io/cluster-api/test/framework?tab=doc#InitManagementCluster
 [Apply method]: https://pkg.go.dev/sigs.k8s.io/cluster-api/test/framework?tab=doc#Applier
-[CAPA E2E tests]: https://github.com/kubernetes-sigs/cluster-api-provider-aws/blob/master/scripts/ci-e2e.sh
+[CAPA E2E tests]: https://github.com/kubernetes-sigs/cluster-api-provider-aws/blob/main/scripts/ci-e2e.sh
 [CAPG E2E tests]: https://github.com/kubernetes-sigs/cluster-api-provider-gcp/blob/master/scripts/ci-e2e.sh
 [WaitForClusterToProvision]: https://pkg.go.dev/sigs.k8s.io/cluster-api/test/framework?tab=doc#WaitForClusterToProvision
 [WaitForKubeadmControlPlaneMachinesToExist]: https://pkg.go.dev/sigs.k8s.io/cluster-api/test/framework?tab=doc#WaitForKubeadmControlPlaneMachinesToExist
 [controller-runtime Client]: https://pkg.go.dev/sigs.k8s.io/[email protected]/pkg/client?tab=doc#Client
 [boskos]: https://git.k8s.io/test-infra/boskos
 [E2E config file]: https://pkg.go.dev/sigs.k8s.io/cluster-api/test/framework/clusterctl?tab=doc#E2EConfig
-[example E2E config file]: https://github.com/kubernetes-sigs/cluster-api/blob/master/test/e2e/config/docker.yaml
+[example E2E config file]: https://github.com/kubernetes-sigs/cluster-api/blob/main/test/e2e/config/docker.yaml
 [NewKindClusterProvider]: https://pkg.go.dev/sigs.k8s.io/cluster-api/test/framework/bootstrap?tab=doc#NewKindClusterProvider
 [InitManagementClusterAndWatchControllerLogs method]: https://pkg.go.dev/sigs.k8s.io/cluster-api/test/framework/clusterctl?tab=doc#InitManagementClusterAndWatchControllerLogs
 [ClusterTemplate method]: https://pkg.go.dev/sigs.k8s.io/cluster-api/test/framework/clusterctl?tab=doc#ConfigCluster

docs/book/src/developer/guide.md

@@ -11,10 +11,10 @@ This guide will walk you through getting that daemon, known as [CAPD], up and ru
 Other providers may have additional steps you need to follow to get up and running.
 
 [capa]: https://github.com/kubernetes-sigs/cluster-api-provider-aws
-[capi-manager]: https://github.com/kubernetes-sigs/cluster-api/blob/master/main.go
-[capa-manager]: https://github.com/kubernetes-sigs/cluster-api-provider-aws/blob/master/main.go
-[Docker]: https://github.com/kubernetes-sigs/cluster-api/tree/master/test/infrastructure/docker
-[CAPD]: https://github.com/kubernetes-sigs/cluster-api/blob/master/test/infrastructure/docker/README.md
+[capi-manager]: https://github.com/kubernetes-sigs/cluster-api/blob/main/main.go
+[capa-manager]: https://github.com/kubernetes-sigs/cluster-api-provider-aws/blob/main/main.go
+[Docker]: https://github.com/kubernetes-sigs/cluster-api/tree/main/test/infrastructure/docker
+[CAPD]: https://github.com/kubernetes-sigs/cluster-api/blob/main/test/infrastructure/docker/README.md
 
 ## Prerequisites
 

docs/book/src/developer/testing.md

@@ -404,4 +404,4 @@ In Cluster API Unit and integration test MUST use [go test].
 [controller-runtime]: https://github.com/kubernetes-sigs/controller-runtime
 [envtest]: https://github.com/kubernetes-sigs/controller-runtime/tree/master/pkg/envtest
 [fakeclient]: https://github.com/kubernetes-sigs/controller-runtime/tree/master/pkg/client/fake
-[test/helpers]: https://github.com/kubernetes-sigs/cluster-api/tree/master/test/helpers
+[test/helpers]: https://github.com/kubernetes-sigs/cluster-api/tree/main/test/helpers

docs/book/src/developer/tilt.md

@@ -188,7 +188,7 @@ tilt up
 This will open the command-line HUD as well as a web browser interface. You can monitor Tilt's status in either
 location. After a brief amount of time, you should have a running development environment, and you should now be able to
 create a cluster. There are [example worker cluster
-configs](https://github.com/kubernetes-sigs/cluster-api/tree/master/test/infrastructure/docker/examples) available.
+configs](https://github.com/kubernetes-sigs/cluster-api/tree/main/test/infrastructure/docker/examples) available.
 These can be customized for your specific needs.
 
 <aside class="note">

docs/book/src/introduction.md

@@ -2,7 +2,7 @@
 
 Cluster API is a Kubernetes sub-project focused on providing declarative APIs and tooling to simplify provisioning, upgrading, and operating multiple Kubernetes clusters.
 
-Started by the Kubernetes Special Interest Group (SIG) [Cluster Lifecycle](https://github.com/kubernetes/community/tree/master/sig-cluster-lifecycle#readme), the Cluster API project uses Kubernetes-style APIs and patterns to automate cluster lifecycle management for platform operators. The supporting infrastructure, like virtual machines, networks, load balancers, and VPCs, as well as the Kubernetes cluster configuration are all defined in the same way that application developers operate deploying and managing their workloads. This enables consistent and repeatable cluster deployments across a wide variety of infrastructure environments.
+Started by the Kubernetes Special Interest Group (SIG) [Cluster Lifecycle](https://github.com/kubernetes/community/tree/main/sig-cluster-lifecycle#readme), the Cluster API project uses Kubernetes-style APIs and patterns to automate cluster lifecycle management for platform operators. The supporting infrastructure, like virtual machines, networks, load balancers, and VPCs, as well as the Kubernetes cluster configuration are all defined in the same way that application developers operate deploying and managing their workloads. This enables consistent and repeatable cluster deployments across a wide variety of infrastructure environments.
 
 ## Getting started
 

docs/book/src/reference/glossary.md

@@ -27,7 +27,7 @@ A temporary cluster that is used to provision a Target Management cluster.
 ---
 
 ### CAEP
-Cluster API Enhancement Proposal - patterned after [KEP](https://git.k8s.io/enhancements/keps/README.md). See [template](https://github.com/kubernetes-sigs/cluster-api/blob/master/docs/proposals/YYYYMMDD-template.md)
+Cluster API Enhancement Proposal - patterned after [KEP](https://git.k8s.io/enhancements/keps/README.md). See [template](https://github.com/kubernetes-sigs/cluster-api/blob/main/docs/proposals/YYYYMMDD-template.md)
 
 ### CAPI
 Core Cluster API

docs/book/src/reference/providers.md

@@ -6,9 +6,9 @@ are also sponsored by SIG Cluster Lifecycle. Check provider's documentation for
 updated info about which API version they are supporting.
 
 ## Bootstrap
-- [Kubeadm](https://github.com/kubernetes-sigs/cluster-api/tree/master/bootstrap/kubeadm)
+- [Kubeadm](https://github.com/kubernetes-sigs/cluster-api/tree/main/bootstrap/kubeadm)
 - [Talos](https://github.com/talos-systems/cluster-api-bootstrap-provider-talos)
-- [EKS](https://github.com/kubernetes-sigs/cluster-api-provider-aws/tree/master/bootstrap/eks)
+- [EKS](https://github.com/kubernetes-sigs/cluster-api-provider-aws/tree/main/bootstrap/eks)
 
 ## Infrastructure
 - [Alibaba Cloud](https://github.com/oam-oss/cluster-api-provider-alicloud)

docs/book/src/tasks/experimental-features/cluster-resource-set.md

@@ -7,4 +7,4 @@ The `ClusterResourceSet` feature is introduced to provide a way to automatically
 **Variable name to enable/disable the feature gate**: `EXP_CLUSTER_RESOURCE_SET`
 
 More details on `ClusterResourceSet` and an example to test it can be found at:
-[ClusterResourceSet CAEP](https://github.com/kubernetes-sigs/cluster-api/blob/master/docs/proposals/20200220-cluster-resource-set.md)
+[ClusterResourceSet CAEP](https://github.com/kubernetes-sigs/cluster-api/blob/main/docs/proposals/20200220-cluster-resource-set.md)

docs/book/src/tasks/experimental-features/machine-pools.md

@@ -22,6 +22,6 @@ each infrastructure provider has a specific solution for orchestrating these `Ma
 Infrastructure providers can support this feature by implementing their specific `MachinePool` such as `AzureMachinePool`.
 
 More details on `MachinePool` can be found at:
-[MachinePool CAEP](https://github.com/kubernetes-sigs/cluster-api/blob/master/docs/proposals/20190919-machinepool-api.md)
+[MachinePool CAEP](https://github.com/kubernetes-sigs/cluster-api/blob/main/docs/proposals/20190919-machinepool-api.md)
 
 For developer docs on the MachinePool controller, see [here](./../../developer/architecture/controllers/machine-pool.md).

docs/book/src/tasks/healthcheck.md

@@ -173,7 +173,7 @@ Explicit skipping using `cluster.x-k8s.io/skip-remediation` annotation:
 Before deploying a MachineHealthCheck, please familiarise yourself with the following limitations and caveats:
 
 - Only Machines owned by a MachineSet or a KubeadmControlPlane can be remediated by a MachineHealthCheck (since a MachineDeployment uses a MachineSet, then this includes Machines that are part of a MachineDeployment)
-- Machines managed by a KubeadmControlPlane are remediated according to [the delete-and-recreate guidelines described in the KubeadmControlPlane proposal](https://github.com/kubernetes-sigs/cluster-api/blob/master/docs/proposals/20191017-kubeadm-based-control-plane.md#remediation-using-delete-and-recreate)
+- Machines managed by a KubeadmControlPlane are remediated according to [the delete-and-recreate guidelines described in the KubeadmControlPlane proposal](https://github.com/kubernetes-sigs/cluster-api/blob/main/docs/proposals/20191017-kubeadm-based-control-plane.md#remediation-using-delete-and-recreate)
 - If the Node for a Machine is removed from the cluster, a MachineHealthCheck will consider this Machine unhealthy and remediate it immediately
 - If no Node joins the cluster for a Machine after the `NodeStartupTimeout`, the Machine will be remediated
 - If a Machine fails for any reason (if the FailureReason is set), the Machine will be remediated immediately

docs/book/src/tasks/kubeadm-bootstrap.md

@@ -7,7 +7,7 @@ for Kubernetes bootstrap.
 
 ### Resources
 
-* [design doc](https://github.com/kubernetes-sigs/cluster-api/blob/master/docs/proposals/20190610-machine-states-preboot-bootstrapping.md)
+* [design doc](https://github.com/kubernetes-sigs/cluster-api/blob/main/docs/proposals/20190610-machine-states-preboot-bootstrapping.md)
 * [The Kubebuilder Book](https://book.kubebuilder.io)
 
 ## How does CABPK work?

docs/book/src/tasks/kubeadm-control-plane.md

@@ -38,7 +38,7 @@ Cluster API Machines:
 - The Kubernetes node hosted on the Machine will be cordoned & drained before removal (with well
   known exceptions like full Cluster deletion).
 - The Machine will respect PreDrainDeleteHook and PreTerminateDeleteHook. see the
-  [Machine Deletion Phase Hooks proposal](https://github.com/kubernetes-sigs/cluster-api/blob/master/docs/proposals/20200602-machine-deletion-phase-hooks.md)
+  [Machine Deletion Phase Hooks proposal](https://github.com/kubernetes-sigs/cluster-api/blob/main/docs/proposals/20200602-machine-deletion-phase-hooks.md)
   for additional details.
 
 <!-- links -->

docs/book/src/user/troubleshooting.md

@@ -21,7 +21,7 @@ be troubleshooted systematically.
 ## Labeling nodes with reserved labels such as `node-role.kubernetes.io` fails with kubeadm error during bootstrap
 
 Self-assigning Node labels such as `node-role.kubernetes.io` using the kubelet `--node-labels` flag
-(see `kubeletExtraArgs` in the [CABPK examples](https://github.com/kubernetes-sigs/cluster-api/tree/master/bootstrap/kubeadm))
+(see `kubeletExtraArgs` in the [CABPK examples](https://github.com/kubernetes-sigs/cluster-api/tree/main/bootstrap/kubeadm))
 is not possible due to a security measure imposed by the
 [`NodeRestriction` admission controller](https://kubernetes.io/docs/reference/access-authn-authz/admission-controllers/#noderestriction)
 that kubeadm enables by default.

docs/proposals/20190919-machinepool-api.md

@@ -70,7 +70,7 @@ status: provisional
 
 ## Glossary
 The lexicon used in this document is described in more detail
-[here](https://github.com/kubernetes-sigs/cluster-api/blob/master/docs/book/src/reference/glossary.md).
+[here](https://github.com/kubernetes-sigs/cluster-api/blob/main/docs/book/src/reference/glossary.md).
 Any discrepancies should be rectified in the main Cluster API glossary.
 
 - **ASG** - AWS Auto Scale Group