provisioner/shell: retry file delete [GH-2286]

provisioner/shell/provisioner.go

@@ -270,7 +270,10 @@ func (p *Provisioner) Provision(ui packer.Ui, comm packer.Communicator) error {
 			return fmt.Errorf("Script exited with non-zero exit status: %d", cmd.ExitStatus)
 		}
 
-		// Delete the temporary file we created
+		// Delete the temporary file we created. We retry this a few times
+		// since if the above rebooted we have to wait until the reboot
+		// completes.
+		err = p.retryable(func() error {
 			cmd = &packer.RemoteCmd{
 				Command: fmt.Sprintf("rm -f %s", p.config.RemotePath),
 			}
@@ -280,6 +283,12 @@ func (p *Provisioner) Provision(ui packer.Ui, comm packer.Communicator) error {
 					p.config.RemotePath, err)
 			}
 			cmd.Wait()
+			return nil
+		})
+		if err != nil {
+			return err
+		}
+
 		if cmd.ExitStatus != 0 {
 			return fmt.Errorf(
 				"Error removing temporary script at %s!",