Changes to OS and package updates as a follow-up on the discussion in…

… PR #169 (#209)

* Changes done as a follow-up on the discussion in PR #169
Removed the step that changes the OS auto-upgrading settings.
Changed the step that installs outside packages such as kubeadm, kubelet and so on to disable auto-upgrading after installing the package.
Updated the tests which are checking for number of completed steps with the new values.

* Removed apt-mark unhold from the undo step as it is not needed and added comments.

agent/installer/installer_test.go

@@ -55,15 +55,15 @@ var _ = Describe("Byohost Installer Tests", func() {
 						i := NewPreviewInstaller(os, &ob)
 						err := i.Install(k8s, testTag)
 						Expect(err).ShouldNot((HaveOccurred()))
-						Expect(ob.LogCalledCnt).Should(Equal(24))
+						Expect(ob.LogCalledCnt).Should(Equal(22))
 					}
 
 					{
 						ob := algo.OutputBuilderCounter{}
 						i := NewPreviewInstaller(os, &ob)
 						err := i.Uninstall(k8s, testTag)
 						Expect(err).ShouldNot((HaveOccurred()))
-						Expect(ob.LogCalledCnt).Should(Equal(24))
+						Expect(ob.LogCalledCnt).Should(Equal(22))
 					}
 				}
 			}

agent/installer/internal/algo/algo_test.go

@@ -15,7 +15,7 @@ var _ = Describe("Installer Algo Tests", func() {
 	)
 
 	const (
-		stepsNum = 24
+		stepsNum = 22
 	)
 
 	BeforeEach(func() {

agent/installer/internal/algo/apt_step.go

@@ -26,8 +26,11 @@ func NewAptStepEx(k *BaseK8sInstaller, aptPkg string, optional bool) Step {
 	if optional {
 		condCmd = fmt.Sprintf("if [ -f %s ]; then %%s; fi", pkgAbsolutePath)
 	}
-
-	doCmd := fmt.Sprintf("dpkg --install '%s'", pkgAbsolutePath)
+	// apt-mark hold will prevent the package from being automatically installed, upgraded or removed.
+	// This is done to prevent unexpected upgrades of the external package in order to ensure that
+	// the working environment is stable. If needed the package can be manually upgraded.
+	doCmd := fmt.Sprintf("dpkg --install '%s' && apt-mark hold %s", pkgAbsolutePath, pkgName)
+	// When uninstalling the package the hold is removed automatically.
 	undoCmd := fmt.Sprintf("dpkg --purge %s", pkgName)
 
 	return &ShellStep{

agent/installer/internal/algo/installer.go

@@ -47,7 +47,6 @@ type K8sStepProvider interface {
 	// os state related steps
 	swapStep(*BaseK8sInstaller) Step
 	firewallStep(*BaseK8sInstaller) Step
-	unattendedUpdStep(*BaseK8sInstaller) Step
 	kernelModsLoadStep(*BaseK8sInstaller) Step
 
 	// packages related steps
@@ -132,7 +131,6 @@ func (b *BaseK8sInstaller) getSteps(bki *BaseK8sInstaller) []Step {
 	var steps = []Step{
 		b.swapStep(bki),
 		b.firewallStep(bki),
-		b.unattendedUpdStep(bki),
 		b.kernelModsLoadStep(bki),
 		b.osWideCfgUpdateStep(bki),
 		b.criToolsStep(bki),

agent/installer/internal/algo/mock_ubuntu_with_error.go

@@ -56,10 +56,6 @@ func (u *MockUbuntuWithError) kernelModsLoadStep(bki *BaseK8sInstaller) Step {
 	return u.getEmptyStep("KERNEL MODULES", bki)
 }
 
-func (u *MockUbuntuWithError) unattendedUpdStep(bki *BaseK8sInstaller) Step {
-	return u.getEmptyStep("AUTO OS UPGRADES", bki)
-}
-
 func (u *MockUbuntuWithError) osWideCfgUpdateStep(bki *BaseK8sInstaller) Step {
 	return u.getEmptyStep("OS CONFIGURATION", bki)
 }

agent/installer/internal/algo/ubuntu20_4K8s1_22.go

@@ -36,14 +36,6 @@ func (u *Ubuntu20_4K8s1_22) kernelModsLoadStep(bki *BaseK8sInstaller) Step {
 		UndoCmd:          "modprobe -r overlay && modprobe -r br_netfilter"}
 }
 
-func (u *Ubuntu20_4K8s1_22) unattendedUpdStep(bki *BaseK8sInstaller) Step {
-	return &ShellStep{
-		BaseK8sInstaller: bki,
-		Desc:             "AUTO OS UPGRADES",
-		DoCmd:            "sed -ri 's/1/0/g' /etc/apt/apt.conf.d/20auto-upgrades",
-		UndoCmd:          "sed -ri 's/0/1/g' /etc/apt/apt.conf.d/20auto-upgrades"}
-}
-
 func (u *Ubuntu20_4K8s1_22) osWideCfgUpdateStep(bki *BaseK8sInstaller) Step {
 	confAbsolutePath := filepath.Join(bki.BundlePath, "conf.tar")