Handle incompatible machines

Start in a reduced mode for recovery, warn, and provide instructions to recreate them

Signed-off-by: Jason T. Greene <jason.greene@redhat.com>

2 files changed, 72 insertions, 44 deletions

diff --git a/cmd/podman/machine/start.go b/cmd/podman/machine/start.go
index 16faa25ef..56acb09cb 100644
--- a/cmd/podman/machine/start.go
+++ b/cmd/podman/machine/start.go
@@ -57,10 +57,6 @@ func start(cmd *cobra.Command, args []string) error {
 		}
 		return errors.Wrapf(machine.ErrMultipleActiveVM, "cannot start VM %s. VM %s is currently running", vmName, activeName)
 	}
-	vm, err = provider.LoadVMByName(vmName)
-	if err != nil {
-		return err
-	}
 	fmt.Printf("Starting machine %q\n", vmName)
 	if err := vm.Start(vmName, machine.StartOptions{}); err != nil {
 		return err
diff --git a/pkg/machine/qemu/machine.go b/pkg/machine/qemu/machine.go
index 3b4548c17..d30e51215 100644
--- a/pkg/machine/qemu/machine.go
+++ b/pkg/machine/qemu/machine.go
@@ -134,7 +134,7 @@ func (p *Provider) NewMachine(opts machine.InitOptions) (machine.VM, error) {
 // LoadByName reads a json file that describes a known qemu vm
 // and returns a vm instance
 func (p *Provider) LoadVMByName(name string) (machine.VM, error) {
-	vm := new(MachineVM)
+	vm := &MachineVM{UID: -1} // posix reserves -1, so use it to signify undefined
 	vmConfigDir, err := machine.GetConfDir(vmtype)
 	if err != nil {
 		return nil, err
@@ -373,6 +373,10 @@ func (v *MachineVM) Start(name string, _ machine.StartOptions) error {
 		wait           time.Duration = time.Millisecond * 500
 	)
 
+	if v.isIncompatible() {
+		logrus.Errorf("machine %q is incompatible with this release of podman and needs to be recreated, starting for recovery only", v.Name)
+	}
+
 	forwardSock, forwardState, err := v.startHostNetworking()
 	if err != nil {
 		return errors.Errorf("unable to start host networking: %q", err)
@@ -506,7 +510,7 @@ func (v *MachineVM) Start(name string, _ machine.StartOptions) error {
 		}
 	}
 
-	waitAPIAndPrintInfo(forwardState, forwardSock, v.Rootful, v.Name)
+	v.waitAPIAndPrintInfo(forwardState, forwardSock)
 
 	return nil
 }
@@ -975,7 +979,11 @@ func (v *MachineVM) startHostNetworking() (string, apiForwardingState, error) {
 	// Add the ssh port
 	cmd = append(cmd, []string{"-ssh-port", fmt.Sprintf("%d", v.Port)}...)
 
-	cmd, forwardSock, state := v.setupAPIForwarding(cmd)
+	var forwardSock string
+	var state apiForwardingState
+	if !v.isIncompatible() {
+		cmd, forwardSock, state = v.setupAPIForwarding(cmd)
+	}
 
 	if logrus.GetLevel() == logrus.DebugLevel {
 		cmd = append(cmd, "--debug")
@@ -1043,6 +1051,10 @@ func (v *MachineVM) setupAPIForwarding(cmd []string) ([]string, string, apiForwa
 	return cmd, dockerSock, dockerGlobal
 }
 
+func (v *MachineVM) isIncompatible() bool {
+	return v.UID == -1
+}
+
 func (v *MachineVM) getForwardSocketPath() (string, error) {
 	path, err := machine.GetDataDir(v.Name)
 	if err != nil {
@@ -1102,46 +1114,66 @@ func waitAndPingAPI(sock string) {
 	}
 }
 
-func waitAPIAndPrintInfo(forwardState apiForwardingState, forwardSock string, rootFul bool, name string) {
-	if forwardState != noForwarding {
-		suffix := ""
-		if name != machine.DefaultMachineName {
-			suffix = " " + name
-		}
-		waitAndPingAPI(forwardSock)
-		if !rootFul {
-			fmt.Printf("\nThis machine is currently configured in rootless mode. If your containers\n")
-			fmt.Printf("require root permissions (e.g. ports < 1024), or if you run into compatibility\n")
-			fmt.Printf("issues with non-podman clients, you can switch using the following command: \n")
-			fmt.Printf("\n\tpodman machine set --rootful%s\n\n", suffix)
-		}
+func (v *MachineVM) waitAPIAndPrintInfo(forwardState apiForwardingState, forwardSock string) {
+	suffix := ""
+	if v.Name != machine.DefaultMachineName {
+		suffix = " " + v.Name
+	}
 
-		fmt.Printf("API forwarding listening on: %s\n", forwardSock)
-		if forwardState == dockerGlobal {
-			fmt.Printf("Docker API clients default to this address. You do not need to set DOCKER_HOST.\n\n")
-		} else {
-			stillString := "still "
-			switch forwardState {
-			case notInstalled:
-				fmt.Printf("\nThe system helper service is not installed; the default Docker API socket\n")
-				fmt.Printf("address can't be used by podman. ")
-				if helper := findClaimHelper(); len(helper) > 0 {
-					fmt.Printf("If you would like to install it run the\nfollowing commands:\n")
-					fmt.Printf("\n\tsudo %s install\n", helper)
-					fmt.Printf("\tpodman machine stop%s; podman machine start%s\n\n", suffix, suffix)
-				}
-			case machineLocal:
-				fmt.Printf("\nAnother process was listening on the default Docker API socket address.\n")
-			case claimUnsupported:
-				fallthrough
-			default:
-				stillString = ""
-			}
+	if v.isIncompatible() {
+		fmt.Fprintf(os.Stderr, "\n!!! ACTION REQUIRED: INCOMPATIBLE MACHINE !!!\n")
 
-			fmt.Printf("You can %sconnect Docker API clients by setting DOCKER_HOST using the\n", stillString)
-			fmt.Printf("following command in your terminal session:\n")
-			fmt.Printf("\n\texport DOCKER_HOST='unix://%s'\n\n", forwardSock)
+		fmt.Fprintf(os.Stderr, "\nThis machine was created by an older podman release that is incompatible\n")
+		fmt.Fprintf(os.Stderr, "with this release of podman. It has been started in a limited operational\n")
+		fmt.Fprintf(os.Stderr, "mode to allow you to copy any necessary files before recreating it. This\n")
+		fmt.Fprintf(os.Stderr, "can be accomplished with the following commands:\n\n")
+		fmt.Fprintf(os.Stderr, "\t# Login and copy desired files (Optional)\n")
+		fmt.Fprintf(os.Stderr, "\t# podman machine ssh%s tar cvPf - /path/to/files > backup.tar\n\n", suffix)
+		fmt.Fprintf(os.Stderr, "\t# Recreate machine (DESTRUCTIVE!) \n")
+		fmt.Fprintf(os.Stderr, "\tpodman machine stop%s\n", suffix)
+		fmt.Fprintf(os.Stderr, "\tpodman machine rm -f%s\n", suffix)
+		fmt.Fprintf(os.Stderr, "\tpodman machine init --now%s\n\n", suffix)
+		fmt.Fprintf(os.Stderr, "\t# Copy back files (Optional)\n")
+		fmt.Fprintf(os.Stderr, "\t# cat backup.tar | podman machine ssh%s tar xvPf - \n\n", suffix)
+	}
+
+	if forwardState == noForwarding {
+		return
+	}
+
+	waitAndPingAPI(forwardSock)
+	if !v.Rootful {
+		fmt.Printf("\nThis machine is currently configured in rootless mode. If your containers\n")
+		fmt.Printf("require root permissions (e.g. ports < 1024), or if you run into compatibility\n")
+		fmt.Printf("issues with non-podman clients, you can switch using the following command: \n")
+		fmt.Printf("\n\tpodman machine set --rootful%s\n\n", suffix)
+	}
+
+	fmt.Printf("API forwarding listening on: %s\n", forwardSock)
+	if forwardState == dockerGlobal {
+		fmt.Printf("Docker API clients default to this address. You do not need to set DOCKER_HOST.\n\n")
+	} else {
+		stillString := "still "
+		switch forwardState {
+		case notInstalled:
+			fmt.Printf("\nThe system helper service is not installed; the default Docker API socket\n")
+			fmt.Printf("address can't be used by podman. ")
+			if helper := findClaimHelper(); len(helper) > 0 {
+				fmt.Printf("If you would like to install it run the\nfollowing commands:\n")
+				fmt.Printf("\n\tsudo %s install\n", helper)
+				fmt.Printf("\tpodman machine stop%s; podman machine start%s\n\n", suffix, suffix)
+			}
+		case machineLocal:
+			fmt.Printf("\nAnother process was listening on the default Docker API socket address.\n")
+		case claimUnsupported:
+			fallthrough
+		default:
+			stillString = ""
 		}
+
+		fmt.Printf("You can %sconnect Docker API clients by setting DOCKER_HOST using the\n", stillString)
+		fmt.Printf("following command in your terminal session:\n")
+		fmt.Printf("\n\texport DOCKER_HOST='unix://%s'\n\n", forwardSock)
 	}
 }