Merge pull request kubernetes#2028 from feiskyer/update-az-kep

Update Out-of-Tree Azure Cloud Provider KEP

Author: k8s-ci-robot

keps/sig-cloud-provider/azure/20190125-out-of-tree-azure.md

@@ -17,7 +17,7 @@ approvers:
   - "@jagosan"
 editor: "@feiskyer"
 creation-date: 2019-01-29
-last-updated: 2020-01-18
+last-updated: 2020-09-29
 status: implementable
 ---
 
@@ -40,8 +40,17 @@ status: implementable
 - [Design Details](#design-details)
   - [Test Plan](#test-plan)
   - [Graduation Criteria](#graduation-criteria)
+    - [Alpha -> Beta Graduation](#alpha---beta-graduation)
+    - [Beta -> GA Graduation](#beta---ga-graduation)
   - [Upgrade / Downgrade Strategy](#upgrade--downgrade-strategy)
   - [Version Skew Strategy](#version-skew-strategy)
+- [Production Readiness Review Questionnaire](#production-readiness-review-questionnaire)
+  - [Feature Enablement and Rollback](#feature-enablement-and-rollback)
+  - [Rollout, Upgrade and Rollback Planning](#rollout-upgrade-and-rollback-planning)
+  - [Monitoring Requirements](#monitoring-requirements)
+  - [Dependencies](#dependencies)
+  - [Scalability](#scalability)
+  - [Troubleshooting](#troubleshooting)
 - [Implementation History](#implementation-history)
 - [Technical Leads are members of the Kubernetes Organization](#technical-leads-are-members-of-the-kubernetes-organization)
 - [Subproject Leads](#subproject-leads)
@@ -50,18 +59,22 @@ status: implementable
 
 ## Release Signoff Checklist
 
-- [X] k/enhancements issue in release milestone and linked to KEP (https://github.com/kubernetes/enhancements/issues/667)
-- [X] KEP approvers have set the KEP status to `implementable`
-- [X] Design details are appropriately documented
-- [X] Test plan is in place, giving consideration to SIG Architecture and SIG Testing input
-- [X] Graduation criteria is in place
-- [X] "Implementation History" section is up-to-date for milestone
-- [X] Supporting documentation e.g., additional design documents, links to mailing list discussions/SIG meetings, relevant PRs/issues, release notes
+Items marked with (R) are required *prior to targeting to a milestone / release*.
+
+- [x] (R) Enhancement issue in release milestone, which links to KEP dir in [kubernetes/enhancements](https://github.com/kubernetes/enhancements/issues/667).
+- [x] (R) KEP approvers have approved the KEP status as `implementable`
+- [x] (R) Design details are appropriately documented
+- [x] (R) Test plan is in place, giving consideration to SIG Architecture and SIG Testing input
+- [x] (R) Graduation criteria is in place
+- [x] (R) Production readiness review completed
+- [x] Production readiness review approved
+- [x] "Implementation History" section is up-to-date for milestone
+- [x] User-facing documentation has been created in [kubernetes-sigs/cloud-provider-azure](https://kubernetes-sigs.github.io/cloud-provider-azure/)
+- [x] Supporting documentation—e.g., additional design documents, links to mailing list discussions/SIG meetings, relevant PRs/issues, release notes
 
 ## Summary
 
-Build support for the out-of-tree Azure cloud provider. This involves a well-tested version of the cloud-controller-manager
-that has feature parity to the kube-controller-manager.
+Build support for the out-of-tree Azure cloud provider. This involves a well-tested version of the cloud-controller-manager that has feature parity to the kube-controller-manager.
 
 ## Motivation
 
@@ -124,7 +137,7 @@ cloud-provider-azure/
 
 - The core of Azure cloud provider would be moved to [kubernetes-sigs/cloud-provider-azure](https://github.com/kubernetes-sigs/cloud-provider-azure).
 - The storage drivers would be moved to [kubernetes-sigs/azuredisk-csi-driver](https://github.com/kubernetes-sigs/azuredisk-csi-driver) and [kubernetes-sigs/azurefile-csi-driver](https://github.com/kubernetes-sigs/azurefile-csi-driver).
-- The credential provider is still under discussion on [kubernetes/cloud-provider#13](https://github.com/kubernetes/cloud-provider/issues/13).
+- The credential provider is tracked by out-of-tree credential provider [KEP](https://github.com/kubernetes/enhancements/blob/master/keps/sig-cloud-provider/20191004-out-of-tree-credential-providers.md) and it won't block the progress of this feature.
 
 ### Risks and Mitigation
 
@@ -162,13 +175,27 @@ See [report](https://testgrid.k8s.io/provider-azure-cloud-provider-azure) for mo
 
 - Azure cloud controller manager is moving to GA
   - Feature compatible with KCM
-  - Conformance tests are passed and published to testgrid
+  - Conformance tests are passed and published to [testgrid](https://testgrid.k8s.io/provider-azure-cloud-provider-azure)
 - CSI drivers for AzureDisk/AzureFile are moving to GA
   - Feature compatible with KCM
-  - Conformance tests are passed and published to testgrid
+  - Features implemented from CSI API SPEC
+  - Conformance tests are passed and published to [testgrid](https://testgrid.k8s.io/provider-azure-azuredisk-csi-driver)
 - Azure credential provider is still supported in Kubelet
   - Feature compatible with KCM
-  - Conformance tests are passed and published to testgrid
+  - Features implemented from CSI API SPEC
+  - Conformance tests are passed and published to [testgrid](https://testgrid.k8s.io/provider-azure-cloud-provider-azure)
+
+#### Alpha -> Beta Graduation
+
+- E2E tests have been added in [testgrid](https://testgrid.k8s.io/provider-azure-cloud-provider-azure)
+- The same set of tests have been passed with out-of-tree projects
+- All the features from in-tree implementations are still supported
+
+#### Beta -> GA Graduation
+
+- Code changes are decoupled from in-tree cloud provide (e.g. it shouldn't vendor in-tree implementations directly)
+- E2E tests have been run stably (e.g. no flaky tests)
+- Upgrade tests and scalability tests have been passed
 
 ### Upgrade / Downgrade Strategy
 
@@ -181,6 +208,136 @@ For each Kubernetes minor releases (e.g. v1.15.x), dedicated Azure cloud control
 - The version matrix for Azure cloud controller manager would be documented on [kubernetes/cloud-provider-azure](https://github.com/kubernetes/cloud-provider-azure/blob/master/README.md#current-status).
 - The version matrix for CSI drivers would be documented on [kubernetes-sigs/azuredisk-csi-driver](https://github.com/kubernetes-sigs/azuredisk-csi-driver#container-images--csi-compatibility) and [kubernetes-sigs/azurefile-csi-driver](https://github.com/kubernetes-sigs/azurefile-csi-driver#container-images--csi-compatibility).
 
+## Production Readiness Review Questionnaire
+
+### Feature Enablement and Rollback
+
+_This section must be completed when targeting alpha to a release._
+
+* **How can this feature be enabled / disabled in a live cluster?**
+  - [x] Feature gate (also fill in values in `kep.yaml`)
+    - Feature gate name: CSIMigrationAzureDisk and CSIMigrationAzureFile
+    - Components depending on the feature gate: kube-controller-manager and kubelet
+  - [x] Other
+    - Describe the mechanism: deploy cloud-controller-manager, cloud-node-manager and CSI drivers in the cluster.
+    - Will enabling / disabling the feature require downtime of the control
+      plane? `--cloud-provider=external` should be set for kube-controller-manager.
+    - Will enabling / disabling the feature require downtime or reprovisioning
+      of a node? --cloud-provider=external` should be set for for kubelet.
+
+* **Does enabling the feature change any default behavior?**
+
+  The default behaviors are still same as before.
+
+* **Can the feature be disabled once it has been enabled (i.e. can we roll back
+  the enablement)?**
+
+  Yes. Delete the cloud-controller-manager and cloud-node-manager, then change the `--cloud-provider`
+  option back to `azure` would still work. CSI drivers should be kept to ensure CSI-provisioned PVCs are still working.
+
+* **What happens if we reenable the feature if it was previously rolled back?**
+
+  It would still work as expected.
+
+* **Are there any tests for feature enablement/disablement?**
+
+  E2E tests have already been added and results are published on testgrid.
+
+### Rollout, Upgrade and Rollback Planning
+
+_This section must be completed when targeting beta graduation to a release._
+
+* **How can a rollout fail? Can it impact already running workloads?**
+
+  Wrong component configurations may cause rollout fail, and running workloads won't be impacted.
+
+* **What specific metrics should inform a rollback?**
+
+  Couldn't create a LoadBalancer typed service or AzureDisk PVC indicate the rollout needs to rollback.
+
+* **Were upgrade and rollback tested? Was the upgrade->downgrade->upgrade path tested?**
+
+  Manually changing the `--cloud-provider` options have been verified. For upgrade->downgrade,
+  the volumes provisioned by CSI drivers should continue to be managed by CSI drivers. They're
+  not able to migrate to in-tree drivers.
+
+* **Is the rollout accompanied by any deprecations and/or removals of features, APIs,
+fields of API types, flags, etc.?**
+
+  In-tree AzureDisk/AzureFile drivers would be migrated to CSI drivers automatically.
+
+### Monitoring Requirements
+
+_This section must be completed when targeting beta graduation to a release._
+
+* **How can an operator determine if the feature is in use by workloads?**
+
+  Operation specific metrics (e.g. LoadBalancer creation and route table update) have been added.
+
+* **What are the SLIs (Service Level Indicators) an operator can use to determine
+the health of the service?**
+  - [x] Metrics
+    - Metric names:
+      - cloudprovider_azure_op_duration_seconds
+      - cloudprovider_azure_api_request_errors
+      - cloudprovider_azure_api_request_throttled_count
+      - cloudprovider_azure_op_duration_seconds_bucket
+    - Components exposing the metric: cloud-controller-manager and CSI drivers
+
+* **What are the reasonable SLOs (Service Level Objectives) for the above SLIs?**
+
+  - 99.5% of read and write ARM requests in the last 5 minutes were successful
+  - LoadBalancer service requests in the last 5 minutes are served in 60 seconds @99th percentile
+  - Routes for new nodes in the last 5 minutes are served in 90 seconds @99th percentile
+  - Disk PVC attach requests in the last 5 minutes are served in 60 seconds @99th percentile
+
+### Dependencies
+
+_This section must be completed when targeting beta graduation to a release._
+
+* **Does this feature depend on any specific services running in the cluster?**
+
+  CSI drivers for AzureDisk/AzureFile are required for out-of-tree cloud provider, 
+  and their plans has already been added in above designs.
+
+### Scalability
+
+_For alpha, this section is encouraged: reviewers should consider these questions
+and attempt to answer them._
+
+_For beta, this section is required: reviewers must answer these questions._
+
+_For GA, this section is required: approvers should be able to confirm the
+previous answers based on experience in the field._
+
+* **Will enabling / using this feature result in any new API calls?**
+
+  Yes, CSI drivers for AzureDisk/AzureFile would be introduced.
+
+* **Will enabling / using this feature result in introducing new API types?**
+
+  Yes, CSI drivers AzureDisk/AzureFile would be introduced.
+
+### Troubleshooting
+
+The Troubleshooting section currently serves the `Playbook` role. We may consider
+splitting it into a dedicated `Playbook` document (potentially with some monitoring
+details). For now, we leave it here.
+
+_This section must be completed when targeting beta graduation to a release._
+
+* **How does this feature react if the API server and/or etcd is unavailable?**
+
+  Same as before.
+
+* **What are other known failure modes?**
+
+  Refer <https://kubernetes-sigs.github.io/cloud-provider-azure/faq>.
+
+* **What steps should be taken if SLOs are not being met to determine the problem?**
+
+  Check the debug logs of cloud-provider-azure since detailed steps are logged in debug level.
+
 ## Implementation History
 
 See [kubernetes/cloud-provider-azure#pulls](https://github.com/kubernetes/cloud-provider-azure/pulls?utf8=%E2%9C%93&q=+is%3Apr+), [kubernetes-sigs/azuredisk-csi-driver#pulls](https://github.com/kubernetes-sigs/azuredisk-csi-driver/pulls?utf8=%E2%9C%93&q=is%3Apr++) and [kubernetes-sigs/azurefile-csi-driver#pulls](https://github.com/kubernetes-sigs/azurefile-csi-driver/pulls?utf8=%E2%9C%93&q=is%3Apr++).