Repository: kubernetes-sigs/cloud-provider-azure
Pull request #4283 (2023-07-13 12:46:14)

[release-1.27] Issue 4230: remove readiness check for cache exclusion
<!--  Thanks for sending a pull request!  Here are some tips for you:

1. If this is your first time, please read our contributor guidelines: https://git.k8s.io/community/contributors/guide/first-contribution.md#your-first-contribution and developer guide https://git.k8s.io/community/contributors/devel/development.md#development-guide
2. Please label this pull request according to what type of issue you are addressing, especially if this is a release targeted pull request. For reference on required PR/issue labels, read here:
https://git.k8s.io/community/contributors/devel/sig-release/release.md#issuepr-kind-label
3. Ensure you have added or ran the appropriate tests for your PR: https://git.k8s.io/community/contributors/devel/sig-testing/testing.md
4. If you want *faster* PR reviews, read how: https://git.k8s.io/community/contributors/guide/pull-requests.md#best-practices-for-faster-reviews
5. If the PR is unfinished, see how to mark it: https://git.k8s.io/community/contributors/guide/pull-requests.md#marking-unfinished-pull-requests
-->

#### What type of PR is this?

<!--
Add one of the following kinds:
/kind bug
/kind cleanup
/kind documentation
/kind feature
/kind design

Optionally add one or more of the following kinds if applicable:
/kind api-change
/kind deprecation
/kind failing-test
/kind flake
/kind regression
-->
/kind bug

#### What this PR does / why we need it:

[release-1.27] cherry-pick of #4234: Cloud provider won't exclude the NotReady nodes from SLB backend pools.


#### Which issue(s) this PR fixes:
<!--
*Automatically closes linked issue when PR is merged.
Usage: `Fixes #<issue number>`, or `Fixes (paste link of issue)`.
_If PR is about `failing-tests or flakes`, please post the related issues/tests in a comment and do not use `Fixes`_*
-->
Fixes #

#### Special notes for your reviewer:

#### Does this PR introduce a user-facing change?
<!--
If no, just write "NONE" in the release-note block below.
If yes, a release note is required:
Enter your extended release note in the block below. If the PR requires additional action from users switching to the new release, include the string "action required".

For more information on release notes see: https://git.k8s.io/community/contributors/guide/release-notes.md
-->
```release-note
Cloud provider won't exclude the NotReady nodes from SLB backend pools
```

#### Additional documentation e.g., KEPs (Kubernetes Enhancement Proposals), usage docs, etc.:

<!--
This section can be blank if this pull request does not require a release note.

When adding links which point to resources within git repositories, like
KEPs or supporting documentation, please reference a specific commit and avoid
linking directly to the master branch. This ensures that links reference a
specific point in time, rather than a document that may change over time.

See here for guidance on getting permanent links to files: https://help.github.com/en/articles/getting-permanent-links-to-files

Please use the following format for linking documentation:
- [KEP]: <link>
- [Usage]: <link>
- [Other doc]: <link>
-->
```docs

```



Patch:
diff --git a/pkg/provider/azure.go b/pkg/provider/azure.go
index e470c41a2..3ddb5a6f9 100644
--- a/pkg/provider/azure.go
+++ b/pkg/provider/azure.go
@@ -75,7 +75,6 @@ import (
 	"sigs.k8s.io/cloud-provider-azure/pkg/azureclients/zoneclient"
 	azcache "sigs.k8s.io/cloud-provider-azure/pkg/cache"
 	"sigs.k8s.io/cloud-provider-azure/pkg/consts"
-	nodemanager "sigs.k8s.io/cloud-provider-azure/pkg/nodemanager"
 	"sigs.k8s.io/cloud-provider-azure/pkg/retry"
 
 	"sigs.k8s.io/yaml"
@@ -1150,14 +1149,6 @@ func (az *Cloud) updateNodeCaches(prevNode, newNode *v1.Node) {
 		case hasExcludeBalancerLabel:
 			az.excludeLoadBalancerNodes.Insert(newNode.ObjectMeta.Name)
 
-		case !isNodeReady(newNode) && nodemanager.GetCloudTaint(newNode.Spec.Taints) == nil:
-			// If not in ready state and not a newly created node, add to excludeLoadBalancerNodes cache.
-			// New nodes (tainted with "node.cloudprovider.kubernetes.io/uninitialized") should not be
-			// excluded from load balancers regardless of their state, so as to reduce the number of
-			// VMSS API calls and not provoke VMScaleSetActiveModelsCountLimitReached.
-			// (https://github.com/kubernetes-sigs/cloud-provider-azure/issues/851)
-			az.excludeLoadBalancerNodes.Insert(newNode.ObjectMeta.Name)
-
 		default:
 			// Nodes not falling into the three cases above are valid backends and
 			// should not appear in excludeLoadBalancerNodes cache.
@@ -1297,12 +1288,3 @@ func (az *Cloud) ShouldNodeExcludedFromLoadBalancer(nodeName string) (bool, erro
 
 	return az.excludeLoadBalancerNodes.Has(nodeName), nil
 }
-
-func isNodeReady(node *v1.Node) bool {
-	for _, cond := range node.Status.Conditions {
-		if cond.Type == v1.NodeReady && cond.Status == v1.ConditionTrue {
-			return true
-		}
-	}
-	return false
-}


Test patch:
diff --git a/pkg/provider/azure_test.go b/pkg/provider/azure_test.go
index 88ae74b37..944f9a781 100644
--- a/pkg/provider/azure_test.go
+++ b/pkg/provider/azure_test.go
@@ -3607,7 +3607,7 @@ func TestUpdateNodeCacheExcludeLoadBalancer(t *testing.T) {
 	az.nodeZones = map[string]sets.Set[string]{zone: nodesInZone}
 	az.nodeResourceGroups = map[string]string{"aNode": "rg"}
 
-	// a non-ready node should be excluded
+	// a non-ready node should be included
 	az.unmanagedNodes = sets.New[string]()
 	az.excludeLoadBalancerNodes = sets.New[string]()
 	az.nodeNames = sets.New[string]()
@@ -3628,9 +3628,9 @@ func TestUpdateNodeCacheExcludeLoadBalancer(t *testing.T) {
 		},
 	}
 	az.updateNodeCaches(nil, &nonReadyNode)
-	assert.Equal(t, 1, len(az.excludeLoadBalancerNodes))
+	assert.Equal(t, 0, len(az.excludeLoadBalancerNodes))
 
-	// node becomes ready, it should be removed from az.excludeLoadBalancerNodes
+	// node becomes ready => no impact on az.excludeLoadBalancerNodes
 	readyNode := v1.Node{
 		ObjectMeta: metav1.ObjectMeta{
 			Labels: map[string]string{