Remove SSM install script from AL2; SSM is pre-installed on EKS AL based AMIs (#8135)

Author: bryantbiggs

pkg/nodebootstrap/README.md

@@ -40,8 +40,6 @@ The call to `UserData` will also dynamically add the following:
 The bootstrap wrapper scripts will use `jq` and `sed` to get user and our config into various files,
 and then call `/etc/eks/bootstrap.sh`.
 
-For AL2, enabling SSM will add `assets/install-ssm.al2.sh`.
-
 ### AmazonLinux2023
 
 While AL2023 implements the `Bootstrapper` interface, the underlying userdata will be entirely different from other AMI families. Specifically, AL2023 introduces a new node initialization process nodeadm that uses a YAML configuration schema, dropping the use of `/etc/eks/bootstrap.sh` script. For self-managed nodes, and for EKS-managed nodes based on custom AMIs, eksctl will populate userdata in the fashion below:
@@ -73,8 +71,6 @@ spec:
 
 ```
 
-For EKS-managed nodes based on native AMIs, the userdata above is fulfilled automatically by the AWS SSM agent.
-
 ## Troubleshooting
 
 ### Ubuntu
@@ -111,5 +107,4 @@ Files:
 /var/lib/cloud/scripts/eksctl/bootstrap.al2.sh
 /etc/kubernetes/kubelet/kubelet-config.json
 /etc/docker/daemon.json
-/var/lib/cloud/scripts/eksctl/install-ssm.sh
 ```

pkg/nodebootstrap/al2_test.go

@@ -31,43 +31,6 @@ var _ = Describe("AmazonLinux2 User Data", func() {
 		}
 	})
 
-	When("SSM is enabled", func() {
-		BeforeEach(func() {
-			ng.SSH.EnableSSM = api.Enabled()
-			bootstrapper = newBootstrapper(clusterConfig, ng)
-		})
-
-		It("does not add the SSM install script to the userdata", func() {
-			userData, err := bootstrapper.UserData()
-			Expect(err).NotTo(HaveOccurred())
-
-			cloudCfg := decode(userData)
-
-			var paths []string
-			for _, f := range cloudCfg.WriteFiles {
-				paths = append(paths, f.Path)
-			}
-			Expect(paths).NotTo(ContainElement("/var/lib/cloud/scripts/eksctl/install-ssm.al2.sh"))
-		})
-	})
-
-	When("EFA is enabled", func() {
-		BeforeEach(func() {
-			enabled := true
-			ng.EFAEnabled = &enabled
-			bootstrapper = newBootstrapper(clusterConfig, ng)
-		})
-
-		It("adds the ssm install script to the userdata", func() {
-			userData, err := bootstrapper.UserData()
-			Expect(err).NotTo(HaveOccurred())
-
-			cloudCfg := decode(userData)
-			Expect(cloudCfg.WriteFiles[2].Path).To(Equal("/var/lib/cloud/scripts/eksctl/bootstrap.al2.sh"))
-			Expect(cloudCfg.WriteFiles[2].Permissions).To(Equal("0755"))
-		})
-	})
-
 	type bootScriptEntry struct {
 		clusterConfig    *api.ClusterConfig
 		ng               *api.NodeGroup

pkg/nodebootstrap/assets/assets.go

@@ -25,11 +25,6 @@ var BootstrapUbuntuSh string
 //go:embed scripts/al2023-xtables.lock.sh
 var AL2023XTablesLock string
 
-// InstallSsmAl2Sh holds the install-ssm.al2.sh contents
-//
-//go:embed scripts/install-ssm.al2.sh
-var InstallSsmAl2Sh string
-
 // KubeletYaml holds the kubelet.yaml contents
 //
 //go:embed scripts/kubelet.yaml