安装和测试xtrabackup8.0
Xtrabackup 2.4.已经不支持MySQL 8.0的备份恢复，使用会报如下错误！
Error: MySQL 8.0 and Percona Server 8.0 are not supported by Percona Xtrabackup 2.4.x series. Please use Percona Xtrabackup 8.0.x for backups and restores.
mysql8.0
[root@enbao ~]# clear
[root@enbao ~]# cat /etc/redhat-release
CentOS Linux release 7.5.1804 (Core)
安装percona-xtrabackup-80
[root@enbao soft]# yum -y install percona-xtrabackup-80-8.0.7-1.el7.x86_64.rpm
Installed:
percona-xtrabackup-80.x86_64 0:8.0.7-1.el7

Complete!
查看安装后结果，发现已经没有innobackupex命令
[root@enbao soft]# rpm -ql percona-xtrabackup-80-8.0.7-1.el7.x86_64
/usr/bin/xbcloud
/usr/bin/xbcloud_osenv
/usr/bin/xbcrypt
/usr/bin/xbstream
/usr/bin/xtrabackup
/usr/lib64/xtrabackup/plugin/keyring_file.so
/usr/lib64/xtrabackup/plugin/keyring_vault.so
/usr/share/doc/percona-xtrabackup-80-8.0.7
/usr/share/doc/percona-xtrabackup-80-8.0.7/LICENSE
/usr/share/man/man1/xbcrypt.1.gz
/usr/share/man/man1/xbstream.1.gz
/usr/share/man/man1/xtrabackup.1.gz
备份3306实例并恢复回3306
创建测试数据
root@enbao 09:56:[enbao]> create database test;
Query OK, 1 row affected (0.06 sec)

root@enbao 09:57:[enbao]> use test;
Database changed
root@enbao 09:57:[test]> create table t1(id int(10) NOT NULL AUTO_INCREMENT,name varchar(20),primary key(id));
Query OK, 0 rows affected, 1 warning (0.09 sec)
root@enbao 09:59:[test]> insert into t1(name) values('a'),('b'),('c');
Query OK, 3 rows affected (0.09 sec)
Records: 3Duplicates: 0Warnings: 0

root@enbao 10:00:[test]> select * from t1;
+----+------+
| id | name |
+----+------+
|1 | a|
|2 | b|
|3 | c|
+----+------+
3 rows in set (0.00 sec)
创建备份目录
[root@enbao data]# mkdir -p /data/backup/
1.xtrabackup --defaults-file=/data/mysql/my3306.cnf-S /data/mysql/mysql3306.sock -uroot -proot123 --backup --no-timestamp --target-dir=/data/backup/db3306_date +%Y%m%d

shutdown 原实例，冷备份原来数据
[root@enbao soft]# mysqladmin -uroot -proot123 shutdown
mv mysql3306 mysql3306_bakmkdir mysql3306/{data,logs,tmp} -p
进行数据恢复xtrabackup --defaults-file=/data/mysql/my3306.cnf--copy-back --target-dir=/data/backup/db3306_20191027/
更改目录权限chown -R mysql:mysql mysql3306/usr/local/mysql/bin/mysqld --defaults-file=/data/mysql/my3306.cnf&
查看error日志是否有错误，登录到数据库验证可用性！
[root@enbao logs]#grep -i "error" /data/mysql/mysql3306/logs/error.log
2019-10-27T10:37:35.389830-04:00 1 [ERROR] [MY-011971] [InnoDB] Tablespace 'innodb_system' Page [page id: space=0, page number=5] log sequence number 29956511 is in the future! Current system log sequence number 29861388.
2019-10-27T10:37:35.389873-04:00 1 [ERROR] [MY-011972] [InnoDB] Your database may be corrupt or you may have copied the InnoDB tablespace but not the InnoDB log files. Please refer to http://dev.mysql.com/doc/refman/8.0/en/forcing-innodb-recovery.html for information about forcing recovery.
[root@enbao logs]# mysql -S /data/mysql/mysql3306.sock -p
Enter password:
Welcome to the MySQL monitor.Commands end with ; or \g.
Your MySQL connection id is 9
Server version: 8.0.17 MySQL Community Server - GPL
root@enbao 11:01:[test]> select * from t1;
+----+------+
| id | name |
+----+------+
|1 | a|
|2 | b|
|3 | c|
+----+------+
3 rows in set (0.00 sec)

root@enbao 11:01:[test]> insert into t1(name) values('d'),('e');
Query OK, 2 rows affected (0.04 sec)
Records: 2Duplicates: 0Warnings: 0