Description of problem:

While upgrading the HE setup from 3.6 to 4.0, the engine-setup within the VM will fail if the db backup file is copied in any place other than /root/.

The script always put the db backup under /root/ in the appliance image.

        g.upload(
            self._backup_src,
            os.path.join('/root/', os.path.basename(self._backup_src))
        )

However while executing the engine-backup command, we are providing backup location as OVEHOSTED_UPGRADE/backupFileName which can change accordingly where the user has put the backup file in the hypervisor.

                engine_restore = (
                    ' - engine-backup --mode=restore --file={backup_file}'
                    ' --log=engine_restore.log --restore-permissions'
                    ' --provision-db {p_dwh_db} {p_reports_db}'
                    ' 1>{port}'
                    ' 2>&1\n'
                    ' - if [ $? -eq 0 ];'
                    ' then echo "{success_string}" >{port};'
                    ' else echo "{fail_string}" >{port};'
                    ' fi\n'
                ).format(
                    backup_file=self.environment[
                        ohostedcons.Upgrade.BACKUP_FILE
                    ],

So the upgrade will fails with below errors.

===
2016-11-14 21:46:18 DEBUG otopi.context context.dumpEnvironment:770 ENV OVEHOSTED_UPGRADE/backupFileName=str:'/tmp/engine_backup.tar.gz'

2016-11-14 19:53:41 DEBUG otopi.plugins.gr_he_common.vm.cloud_init cloud_init._misc:869 engine_restore:  - engine-backup --mode=restore --file=/tmp/engine_backup.tar.gz --log=engine_restore.log --restore-permissions --provision-db   1>/dev/virtio-ports/org.ovirt.hosted-engine-setup.0 2>&1
 - if [ $? -eq 0 ]; then echo "HE_APPLIANCE_ENGINE_RESTORE_SUCCESS" >/dev/virtio-ports/org.ovirt.hosted-engine-setup.0; else echo "HE_APPLIANCE_ENGINE_RESTORE_FAIL" >/dev/virtio-ports/org.ovirt.hosted-engine-setup.0; fi


 2016-11-14 21:46:18 DEBUG otopi.plugins.otopi.dialog.human dialog.__logString:204 DIALOG:SEND                 |- FATAL: /tmp/engine_backup.tar.gz does not exist
2016-11-14 21:46:18 DEBUG otopi.plugins.otopi.dialog.human dialog.__logString:204 DIALOG:SEND                 |- HE_APPLIANCE_ENGINE_RESTORE_FAIL
2016-11-14 21:46:18 ERROR otopi.plugins.gr_he_common.engine.health health._closeup:157 Engine backup restore failed on the appliance
===

Version-Release number of selected component (if applicable):

rhevm-4.0.4.4-0.1.el7ev.noarch
ovirt-hosted-engine-setup-2.0.2.2-2.el7ev.noarch

How reproducible:

100%

Steps to Reproduce:

1. Put the DB backup in any location other than /root/

2.  Run hosted-engine --upgrade-appliance and this fail with error

Actual results:

hosted-engine --upgrade-appliance is not working

Expected results:

hosted-engine --upgrade-appliance should be working irrespective of the backup file location.

Additional info: