def restore_instance(backup_type, restore_source, destination,
                     no_repl, date,
                     add_to_zk, skip_production_check):
    """ Restore a MySQL backup on to localhost

    Args:
    backup_type - Type of backup to restore
    restore_source - A hostaddr object for where to pull a backup from
    destination -  A hostaddr object for where to restore the backup
    no_repl - Should  replication be not started. It will always be setup.
    date - What date should the backup be from
    add_to_zk - Should the instnace be added to zk. If so, the log from the
                host being launched will be consulted.
    skip_production_check - Do not check if the host is already in zk for
                            production use.
    """
    log.info('Supplied source is {source}'.format(source=restore_source))
    log.info('Supplied destination is {dest}'.format(dest=destination))
    log.info('Desired date of restore {date}'.format(date=date))
    zk = host_utils.MysqlZookeeper()

    # Try to prevent unintentional destruction of prod servers
    log.info('Confirming no prod instances running on destination')
    prod_check(destination, skip_production_check)

    # Take a lock to prevent multiple restores from running concurrently
    log.info('Taking a lock to block another restore from starting')
    lock_handle = host_utils.bind_lock_socket(backup.STD_BACKUP_LOCK_SOCKET)

    log.info('Looking for a backup to restore')
    if restore_source:
        possible_sources = [restore_source]
    else:
        possible_sources = get_possible_sources(destination, backup_type)
    backup_key = find_a_backup_to_restore(possible_sources, destination,
                                          backup_type, date)

    # Figure out what what we use to as the master when we setup replication
    (restore_source, _) = backup.get_metadata_from_backup_file(backup_key.name)
    try:
        replica_set = restore_source.get_zk_replica_set()
        master = zk.get_mysql_instance_from_replica_set(replica_set,
                                                        host_utils.REPLICA_ROLE_MASTER)
    except:
        # ZK has no idea what this replica set is, probably a new replica set.
        master = restore_source

    # Start logging
    row_id = backup.start_restore_log(master, {
                'restore_source': restore_source,
                'restore_port': destination.port,
                'restore_file': backup_key.name,
                'source_instance': destination.hostname,
                'restore_date': date,
                'replication': no_repl,
                'zookeeper': add_to_zk})

    # Giant try to allow logging if anything goes wrong.
    try:
        # If we hit an exception, this status will be used. If not, it will
        # be overwritten
        restore_log_update = {'restore_status': 'BAD'}

        # This also ensures that all needed directories exist
        log.info('Rebuilding local mysql instance')
        lock_handle = mysql_init_server.mysql_init_server(
                        destination,
                        skip_production_check=True,
                        skip_backup=True,
                        lock_handle=lock_handle)

        if backup_type == backup.BACKUP_TYPE_XBSTREAM:
            xbstream_restore(backup_key, destination.port)
            if master == restore_source:
                log.info('Pulling replication info for restore from '
                         'backup source')
                (binlog_file,
                 binlog_pos,
                 gtid_purged) = backup.parse_xtrabackup_binlog_info(
                                destination.port)
            else:
                log.info('Pulling replication info for restore from '
                         'master of backup source')
                # if our backup came from a GTID server, we won't have
                # a binlog_file and a binlog_pos, so we need to see if
                # we can get a set of purged GTIDs
                (binlog_file,
                 binlog_pos,
                 gtid_purged) = backup.parse_xtrabackup_slave_info(
                                destination.port)

        elif backup_type == backup.BACKUP_TYPE_LOGICAL:
            log.info('Preparing replication')
            # We are importing a mysqldump which was created with
            # --master-data or --dump-slave so there will be a CHANGE MASTER
            # statement at the start of the dump. MySQL will basically just
            # ignore a CHANGE MASTER command if master_host is not already
            # setup. So we are setting master_host, username and password
            # here. We use BOGUS for master_log_file so that the IO thread is
            # intentionally broken.  With no argument for master_log_file,
            # the IO thread would start downloading the first bin log and
            # the SQL thread would start executing...
            mysql_lib.change_master(destination, master, 'BOGUS', 0,
                                    no_start=True)
            # reset master on slave before we load anything to ensure that
            # we can set GTID info from the backup, if it exists.
            mysql_lib.reset_master(destination)
            logical_restore(backup_key, destination)
            host_utils.stop_mysql(destination.port)

        log.info('Running MySQL upgrade')
        host_utils.upgrade_auth_tables(destination.port)

        log.info('Starting MySQL')
        host_utils.start_mysql(
            destination.port,
            options=host_utils.DEFAULTS_FILE_EXTRA_ARG.format(
                defaults_file=host_utils.MYSQL_NOREPL_CNF_FILE))

        # Since we haven't started the slave yet, make sure we've got these
        # plugins installed, whether we use them or not.
        mysql_lib.setup_semisync_plugins(destination)
        mysql_lib.setup_audit_plugin(destination)
        mysql_lib.setup_response_time_metrics(destination)

        restore_log_update = {'restore_status': 'OK'}

        # Try to configure replication.
        log.info('Setting up MySQL replication')
        restore_log_update['replication'] = 'FAIL'
        if backup_type == backup.BACKUP_TYPE_XBSTREAM:
            # before we change master, reset master on the
            # slave to clear out any GTID errant transactions.
            mysql_lib.reset_master(destination)
            mysql_lib.change_master(destination,
                                    master,
                                    binlog_file,
                                    binlog_pos,
                                    gtid_purged=gtid_purged,
                                    no_start=(no_repl == 'SKIP'))
        elif backup_type == backup.BACKUP_TYPE_LOGICAL:
            if no_repl == 'SKIP':
                log.info('As requested, not starting replication.')
            else:
                mysql_lib.restart_replication(destination)
        if no_repl == 'REQ':
            mysql_lib.wait_for_catch_up(destination)
        restore_log_update['replication'] = 'OK'

        host_utils.manage_pt_daemons(destination.port)

    except Exception as e:
        log.error(e)
        if row_id is not None:
            restore_log_update['status_message'] = e
            restore_log_update['finished_at'] = True
        raise
    finally:
        # As with mysql_init_server, we have to do one more restart to
        # clear out lock ownership, but here we have to also do it with
        # the proper config file.
        if lock_handle:
            log.info('Releasing lock and restarting MySQL')
            host_utils.stop_mysql(destination.port)
            time.sleep(5)
            host_utils.release_lock_socket(lock_handle)
            if no_repl == 'SKIP':
                host_utils.start_mysql(
                    destination.port,
                    options=host_utils.DEFAULTS_FILE_EXTRA_ARG.format(
                        defaults_file=host_utils.MYSQL_NOREPL_CNF_FILE))
            else:
                host_utils.start_mysql(destination.port)

        backup.update_restore_log(master, row_id, restore_log_update)

    try:
        if add_to_zk == 'REQ':
            if no_repl == 'REQ':
                log.info('Waiting for replication again, as it may have '
                         'drifted due to restart.')
                mysql_lib.wait_for_catch_up(destination)
                log.info('Waiting for IO lag in case it is still too '
                         'far even wait for resync ')
                mysql_lib.wait_for_catch_up(destination, io=True)
            log.info('Adding instance to zk.')
            modify_mysql_zk.auto_add_instance_to_zk(destination.port,
                                                    dry_run=False)
            backup.update_restore_log(master, row_id, {'zookeeper': 'OK'})
        else:
            log.info('add_to_zk is not set, therefore not adding to zk')
    except Exception as e:
        log.warning("An exception occurred: {}".format(e))
        log.warning("If this is a DB issue, that's fine. "
                    "Otherwise, you should check ZK.")
    backup.update_restore_log(master, row_id, {'finished_at': True})

    if no_repl == 'REQ':
        log.info('Starting a new backup')
        mysql_backup.mysql_backup(destination, initial_build=True)
Пример #2
0
def restore_instance(backup_type, restore_source, destination,
                     no_repl, date,
                     add_to_zk, skip_production_check):
    """ Restore a MySQL backup on to localhost

    Args:
    backup_type - Type of backup to restore
    restore_source - A hostaddr object for where to pull a backup from
    destination -  A hostaddr object for where to restore the backup
    no_repl - Should  replication be not started. It will always be setup.
    date - What date should the backup be from
    add_to_zk - Should the instnace be added to zk. If so, the log from the
                host being launched will be consulted.
    skip_production_check - Do not check if the host is already in zk for
                            production use.
    """
    log.info('Supplied source is {source}'.format(source=restore_source))
    log.info('Supplied destination is {dest}'.format(dest=destination))
    log.info('Desired date of restore {date}'.format(date=date))
    zk = host_utils.MysqlZookeeper()

    # Try to prevent unintentional destruction of prod servers
    log.info('Confirming no prod instances running on destination')
    prod_check(destination, skip_production_check)

    # Take a lock to prevent multiple restores from running concurrently
    log.info('Taking a flock to block another restore from starting')
    lock_handle = host_utils.take_flock_lock(backup.BACKUP_LOCK_FILE)

    log.info('Looking for a backup to restore')
    if restore_source:
        possible_sources = [restore_source]
    else:
        possible_sources = get_possible_sources(destination, backup_type)
    backup_key = find_a_backup_to_restore(possible_sources, destination,
                                          backup_type, date)

    # Figure out what what we use to as the master when we setup replication
    (restore_source, _) = backup.get_metadata_from_backup_file(backup_key.name)
    if restore_source.get_zk_replica_set():
        replica_set = restore_source.get_zk_replica_set()[0]
        master = zk.get_mysql_instance_from_replica_set(replica_set, host_utils.REPLICA_ROLE_MASTER)
    else:
        # ZK has no idea what this replica set is, probably a new replica set.
        master = restore_source

    # Start logging
    row_id = backup.start_restore_log(master, {'restore_source': restore_source,
                                               'restore_port': destination.port,
                                               'restore_file': backup_key.name,
                                               'source_instance': destination.hostname,
                                               'restore_date': date,
                                               'replication': no_repl,
                                               'zookeeper': add_to_zk})
    # Giant try to allow logging if anything goes wrong.
    try:
        # If we hit an exception, this status will be used. If not, it will
        # be overwritten
        restore_log_update = {'restore_status': 'BAD'}

        # This also ensures that all needed directories exist
        log.info('Rebuilding local mysql instance')
        mysql_init_server.mysql_init_server(destination, skip_production_check=True,
                                            skip_backup=True, skip_locking=True)

        if backup_type == backup.BACKUP_TYPE_XBSTREAM:
            xbstream_restore(backup_key, destination.port)
            if master == restore_source:
                log.info('Pulling replication info from restore to backup source')
                (binlog_file, binlog_pos) = backup.parse_xtrabackup_binlog_info(destination.port)
            else:
                log.info('Pulling replication info from restore to '
                         'master of backup source')
                (binlog_file, binlog_pos) = backup.parse_xtrabackup_slave_info(destination.port)
        elif backup_type == backup.BACKUP_TYPE_LOGICAL:
            logical_restore(backup_key, destination)
            host_utils.stop_mysql(destination.port)

        log.info('Running MySQL upgrade')
        host_utils.upgrade_auth_tables(destination.port)

        log.info('Starting MySQL')
        host_utils.start_mysql(destination.port,
                               options=host_utils.DEFAULTS_FILE_EXTRA_ARG.format(defaults_file=host_utils.MYSQL_NOREPL_CNF_FILE))

        # Since we haven't started the slave yet, make sure we've got these
        # plugins installed, whether we use them or not.
        mysql_lib.setup_semisync_plugins(destination)
        restore_log_update = {'restore_status': 'OK'}

        # Try to configure replication.
        log.info('Setting up MySQL replication')
        restore_log_update['replication'] = 'FAIL'
        if backup_type == backup.BACKUP_TYPE_XBSTREAM:
            mysql_lib.change_master(destination,
                                    master,
                                    binlog_file,
                                    binlog_pos,
                                    no_start=(no_repl == 'SKIP'))
        elif backup_type == backup.BACKUP_TYPE_LOGICAL:
            if no_repl == 'SKIP':
                log.info('As requested, not starting replication.')
            else:
                mysql_lib.restart_replication(destination)
        if no_repl == 'REQ':
            mysql_lib.wait_replication_catch_up(destination)
        restore_log_update['replication'] = 'OK'

        host_utils.restart_pt_daemons(destination.port)
        mysql_lib.setup_response_time_metrics(destination)

    except Exception as e:
        log.error(e)
        if row_id is not None:
            restore_log_update['status_message'] = e
            restore_log_update['finished_at'] = True
        raise
    finally:
        if lock_handle:
            log.info('Releasing lock')
            host_utils.release_flock_lock(lock_handle)
        backup.update_restore_log(master, row_id, restore_log_update)

    try:
        if add_to_zk == 'REQ':
            log.info('Adding instance to zk')
            modify_mysql_zk.auto_add_instance_to_zk(destination.port,
                                                    dry_run=False)
            backup.update_restore_log(master, row_id, {'zookeeper': 'OK'})
        else:
            log.info('add_to_zk is not set, therefore not adding to zk')
    except Exception as e:
        log.warning("An exception occurred: {e}".format(e=e))
        log.warning("If this is a DB issue, that's fine. "
                    "Otherwise, you should check ZK.")
    backup.update_restore_log(master, row_id, {'finished_at': True})

    if no_repl == 'REQ':
        log.info('Starting a new backup')
        mysql_backup.mysql_backup(destination, initial_build=True)
def restore_instance(restore_source, destination, restore_type,
                     restore_file, no_repl, date,
                     add_to_zk, skip_production_check,
                     test_restore):
    """ Restore a MySQL backup on to localhost

    Args:
    restore_source - A hostaddr object for where to pull a backup from
    destination -  A hostaddr object for where to restore the backup
    restore_type - How to pull the backup, options are 's3', 'remote_server'
                   and 'local_file'
    no_repl - Should  replication be not started. It will always be setup.
    date - What date should the backup be from
    add_to_zk - Should the instnace be added to zk. If so, the log from the
                host being launched will be consulted.
    skip_production_check - Do not check if the host is already in zk for
                            production use.
    test_restore - Use less ram and shutdown the instance after going
                   through the motions of a restore.
    """
    (temp_dir, target_dir) = backup.get_paths(str(destination.port))
    log.info('Supplied source is {source}'.format(source=restore_source))
    log.info('Supplied destination is {dest}'.format(dest=destination))
    log.info('Restore type is {rest}'.format(rest=restore_type))
    log.info('Local restore file is {file}'.format(file=restore_file))
    log.info('Desired date of restore {date}'.format(date=date))
    if test_restore == 'test':
        log.info('Running restore in test mode')

    # Try to prevent unintentional destruction of prod servers
    zk = host_utils.MysqlZookeeper()
    try:
        (_, replica_type) = zk.get_replica_set_from_instance(destination)
    except:
        # instance is not in production
        replica_type = None
    if replica_type == host_utils.REPLICA_ROLE_MASTER:
        # If the instance, we will refuse to run. No ifs, ands, or buts/
        raise Exception('Restore script must never run on a master')
    if replica_type:
        if skip_production_check:
            log.info('Ignoring production check. We hope you know what you '
                     'are doing and we will try to take a backup in case '
                     'you are wrong.')
            try:
                mysql_backup.mysql_backup(destination)
            except Exception as e:
                log.error(e)
                log.warning('Unable to take a backup. We will give you {time} '
                            'seconds to change your mind and ^c.'
                            ''.format(time=SCARY_TIMEOUT))
                time.sleep(SCARY_TIMEOUT)
        else:
            raise Exception("It appears {instance} is in use. This is"
                            " very dangerous!".format(instance=destination))

    # Take a lock to prevent multiple restores from running concurrently
    log.info('Taking a flock to block another restore from starting')
    lock_handle = host_utils.take_flock_lock(backup.BACKUP_LOCK_FILE)

    log.info('Rebuilding cnf files just in case')
    mysql_cnf_builder.build_cnf()

    mysql_init_server.create_and_chown_dirs(destination.port)

    # load some data from the mysql conf file
    datadir = host_utils.get_cnf_setting('datadir', destination.port)

    # Where will we look for a backup?
    if restore_type != 'local_file':
        (restore_type, restore_source,
         restore_file, restore_size) = find_a_backup_to_restore(restore_type, restore_source,
                                                                destination, date)
    # Not using an if/else because find_a_backup_to_restore could set to
    # local_file if the file has already been downloaded.
    if restore_type == 'local_file':
        restore_source = backup.get_host_from_backup(restore_file)
        # restore_size will be computed in the unpack function
        restore_size = None
        log.info('Detected the source of backup as {src}'.format(src=restore_source))

    if restore_source.get_zk_replica_set():
        replica_set = restore_source.get_zk_replica_set()[0]
        master = zk.get_mysql_instance_from_replica_set(replica_set, host_utils.REPLICA_ROLE_MASTER)
    else:
        # ZK has no idea what this replica set is, probably a new replica set.
        master = restore_source

    # Start logging
    row_id = backup.start_restore_log(master, {'restore_type': restore_type,
                                               'test_restore': test_restore,
                                               'restore_source': restore_source,
                                               'restore_port': destination.port,
                                               'restore_file': restore_file,
                                               'source_instance': destination.hostname,
                                               'restore_date': date,
                                               'replication': no_repl,
                                               'zookeeper': add_to_zk})
    # Giant try to allow logging if anything goes wrong.
    try:
        # If we hit an exception, this status will be used. If not, it will
        # be overwritten
        restore_log_update = {'restore_status': 'BAD'}
        log.info('Quick sanity check')
        mysql_init_server.basic_host_sanity()

        log.info('Shutting down MySQL')
        host_utils.stop_mysql(destination.port)

        log.info('Removing any existing MySQL data')
        mysql_init_server.delete_mysql_data(destination.port)

        log.info('Unpacking {rfile} into {ddir}'.format(rfile=restore_file,
                                                        ddir=datadir))
        backup.xbstream_unpack(restore_file, destination.port,
                               restore_source, restore_type, restore_size)

        log.info('Decompressing files in {path}'.format(path=datadir))
        backup.innobackup_decompress(destination.port)

        log.info('Applying logs')
        if test_restore == 'test':
            # We don't really need a lot of memory if we're just
            # verifying that it works.
            backup.apply_log(destination.port, memory='1G')
        else:
            backup.apply_log(destination.port, memory='10G')

        log.info('Removing old innodb redo logs')
        mysql_init_server.delete_innodb_log_files(destination.port)

        log.info('Setting permissions for MySQL on {dir}'.format(dir=datadir))
        host_utils.change_owner(datadir, 'mysql', 'mysql')

        log.info('Starting MySQL')
        host_utils.upgrade_auth_tables(destination.port)
        restore_log_update = {'restore_status': 'OK'}

        log.info('Running MySQL upgrade')
        host_utils.start_mysql(destination.port,
                               options=host_utils.DEFAULTS_FILE_EXTRA_ARG.format(defaults_file=host_utils.MYSQL_NOREPL_CNF_FILE))

        if master == backup.get_host_from_backup(restore_file):
            log.info('Pulling replication info from restore to backup source')
            (binlog_file, binlog_pos) = backup.parse_xtrabackup_binlog_info(datadir)
        else:
            log.info('Pulling replication info from restore to '
                     'master of backup source')
            (binlog_file, binlog_pos) = backup.parse_xtrabackup_slave_info(datadir)

        log.info('Setting up MySQL replication')
        restore_log_update['replication'] = 'FAIL'

        # Since we haven't started the slave yet, make sure we've got these
        # plugins installed, whether we use them or not.
        mysql_lib.setup_semisync_plugins(destination)

        # Try to configure replication.  If this was just a test restore,
        # don't wait for it to catch up - don't even start the slave.
        if test_restore == 'test':
            mysql_lib.change_master(destination,
                                    master,
                                    binlog_file,
                                    binlog_pos,
                                    no_start=True)
            backup.quick_test_replication(destination)
        else:
            mysql_lib.change_master(destination,
                                    master,
                                    binlog_file,
                                    binlog_pos,
                                    no_start=(no_repl == 'SKIP'))
            mysql_lib.wait_replication_catch_up(destination)
            host_utils.restart_pt_daemons(destination.port)

        restore_log_update['replication'] = 'OK'

        mysql_lib.setup_response_time_metrics(destination)

    except Exception as e:
        log.error(e)
        if row_id is not None:
            restore_log_update['status_message'] = e
            restore_log_update['finished_at'] = True
        raise
    finally:
        if lock_handle:
            log.info('Releasing lock')
            host_utils.release_flock_lock(lock_handle)
        backup.update_restore_log(master, row_id, restore_log_update)

    # If this was a test restore, we don't need to keep the 3307
    # instance running, so let's shut it off.
    if test_restore == 'test':
        log.info('Shutting down MySQL backup/restore test instance')
        host_utils.stop_mysql(destination.port)
        backup.update_restore_log(master, row_id, {'finished_at': True})
        return

    try:
        if add_to_zk == 'REQ':
            log.info('Adding instance to zk')
            modify_mysql_zk.auto_add_instance_to_zk(destination, dry_run=False)
            backup.update_restore_log(master, row_id, {'zookeeper': 'OK'})
        else:
            log.info('add_to_zk is not set, therefore not adding to zk')
    except Exception as e:
        log.warning("An exception occurred: {e}".format(e=e))
        log.warning("If this is a DB issue, that's fine. "
                    "Otherwise, you should check ZK.")

    backup.update_restore_log(master, row_id, {'finished_at': True})
    log.info('Starting a new backup')
    mysql_backup.mysql_backup(destination)
def restore_instance(restore_source, destination, no_repl, date, add_to_zk,
                     skip_production_check):
    """ Restore a MySQL backup on to localhost

    Args:
    restore_source - A hostaddr object for where to pull a backup from
    destination -  A hostaddr object for where to restore the backup
    no_repl - Should  replication be not started. It will always be setup.
    date - What date should the backup be from
    add_to_zk - Should the instnace be added to zk. If so, the log from the
                host being launched will be consulted.
    skip_production_check - Do not check if the host is already in zk for
                            production use.
    """
    log.info('Supplied source is {source}'.format(source=restore_source))
    log.info('Supplied destination is {dest}'.format(dest=destination))
    log.info('Desired date of restore {date}'.format(date=date))

    # Try to prevent unintentional destruction of prod servers
    zk = host_utils.MysqlZookeeper()
    try:
        (_, replica_type) = zk.get_replica_set_from_instance(destination)
    except:
        # instance is not in production
        replica_type = None
    if replica_type == host_utils.REPLICA_ROLE_MASTER:
        # If the instance, we will refuse to run. No ifs, ands, or buts/
        raise Exception('Restore script must never run on a master')
    if replica_type:
        if skip_production_check:
            log.info('Ignoring production check. We hope you know what you '
                     'are doing and we will try to take a backup in case '
                     'you are wrong.')
            try:
                mysql_backup.mysql_backup(destination)
            except Exception as e:
                log.error(e)
                log.warning('Unable to take a backup. We will give you {time} '
                            'seconds to change your mind and ^c.'
                            ''.format(time=SCARY_TIMEOUT))
                time.sleep(SCARY_TIMEOUT)
        else:
            raise Exception("It appears {instance} is in use. This is"
                            " very dangerous!".format(instance=destination))

    # Take a lock to prevent multiple restores from running concurrently
    log.info('Taking a flock to block another restore from starting')
    lock_handle = host_utils.take_flock_lock(backup.BACKUP_LOCK_FILE)

    log.info('Rebuilding cnf files just in case')
    mysql_cnf_builder.build_cnf()

    mysql_init_server.create_and_chown_dirs(destination.port)

    # load some data from the mysql conf file
    datadir = host_utils.get_cnf_setting('datadir', destination.port)

    (restore_source, restore_file,
     restore_size) = find_a_backup_to_restore(restore_source, destination,
                                              date)
    if restore_source.get_zk_replica_set():
        replica_set = restore_source.get_zk_replica_set()[0]
        master = zk.get_mysql_instance_from_replica_set(
            replica_set, host_utils.REPLICA_ROLE_MASTER)
    else:
        # ZK has no idea what this replica set is, probably a new replica set.
        master = restore_source

    # Start logging
    row_id = backup.start_restore_log(
        master, {
            'restore_source': restore_source,
            'restore_port': destination.port,
            'restore_file': restore_file,
            'source_instance': destination.hostname,
            'restore_date': date,
            'replication': no_repl,
            'zookeeper': add_to_zk
        })
    # Giant try to allow logging if anything goes wrong.
    try:
        # If we hit an exception, this status will be used. If not, it will
        # be overwritten
        restore_log_update = {'restore_status': 'BAD'}
        log.info('Quick sanity check')
        mysql_init_server.basic_host_sanity()

        log.info('Shutting down MySQL')
        host_utils.stop_mysql(destination.port)

        log.info('Removing any existing MySQL data')
        mysql_init_server.delete_mysql_data(destination.port)

        log.info('Unpacking {rfile} into {ddir}'.format(rfile=restore_file,
                                                        ddir=datadir))
        backup.xbstream_unpack(restore_file, destination.port, restore_source,
                               restore_size)

        log.info('Decompressing files in {path}'.format(path=datadir))
        backup.innobackup_decompress(destination.port)

        # Determine how much RAM to use for applying logs based on the
        # system's total RAM size; all our boxes have 32G or more, so
        # this will always be better than before, but not absurdly high.
        log_apply_ram = psutil.phymem_usage()[0] / 1024 / 1024 / 1024 / 3
        log.info('Applying logs')
        backup.apply_log(destination.port, memory='{}G'.format(log_apply_ram))

        log.info('Removing old innodb redo logs')
        mysql_init_server.delete_innodb_log_files(destination.port)

        log.info('Setting permissions for MySQL on {dir}'.format(dir=datadir))
        host_utils.change_owner(datadir, 'mysql', 'mysql')

        log.info('Starting MySQL')
        host_utils.upgrade_auth_tables(destination.port)
        restore_log_update = {'restore_status': 'OK'}

        log.info('Running MySQL upgrade')
        host_utils.start_mysql(
            destination.port,
            options=host_utils.DEFAULTS_FILE_EXTRA_ARG.format(
                defaults_file=host_utils.MYSQL_NOREPL_CNF_FILE))

        if master == backup.get_metadata_from_backup_file(restore_file)[0]:
            log.info('Pulling replication info from restore to backup source')
            (binlog_file,
             binlog_pos) = backup.parse_xtrabackup_binlog_info(datadir)
        else:
            log.info('Pulling replication info from restore to '
                     'master of backup source')
            (binlog_file,
             binlog_pos) = backup.parse_xtrabackup_slave_info(datadir)

        log.info('Setting up MySQL replication')
        restore_log_update['replication'] = 'FAIL'

        # Since we haven't started the slave yet, make sure we've got these
        # plugins installed, whether we use them or not.
        mysql_lib.setup_semisync_plugins(destination)

        # Try to configure replication.
        mysql_lib.change_master(destination,
                                master,
                                binlog_file,
                                binlog_pos,
                                no_start=(no_repl == 'SKIP'))
        mysql_lib.wait_replication_catch_up(destination)
        host_utils.restart_pt_daemons(destination.port)

        restore_log_update['replication'] = 'OK'

        mysql_lib.setup_response_time_metrics(destination)

    except Exception as e:
        log.error(e)
        if row_id is not None:
            restore_log_update['status_message'] = e
            restore_log_update['finished_at'] = True
        raise
    finally:
        if lock_handle:
            log.info('Releasing lock')
            host_utils.release_flock_lock(lock_handle)
        backup.update_restore_log(master, row_id, restore_log_update)

    try:
        if add_to_zk == 'REQ':
            log.info('Adding instance to zk')
            modify_mysql_zk.auto_add_instance_to_zk(destination, dry_run=False)
            backup.update_restore_log(master, row_id, {'zookeeper': 'OK'})
        else:
            log.info('add_to_zk is not set, therefore not adding to zk')
    except Exception as e:
        log.warning("An exception occurred: {e}".format(e=e))
        log.warning("If this is a DB issue, that's fine. "
                    "Otherwise, you should check ZK.")

    backup.update_restore_log(master, row_id, {'finished_at': True})
    log.info('Starting a new backup')
    mysql_backup.mysql_backup(destination)