[Xtrabackup] failed to execute query ‘LOCK INSTANCE FOR BACKUP’ : 1227 (42000) Access denied; you need (at least one of) the BACKUP_ADMIN privilege(s) for this operation

xtrabackup备份时报错：
[Xtrabackup] failed to execute query ‘LOCK INSTANCE FOR BACKUP’ : 1227 (42000) Access denied; you need (at least one of) the BACKUP_ADMIN privilege(s) for this operation
解决方案：
进入mysql
赋予权限
mysql> grant BACKUP_ADMIN on *.* to root@'%';
flush privileges;