Xtrabackup备份恢复MySQL从库

xtrabackup的流备份恢复MySQL从库步骤

主库上授权 (如果无授权)

grant reload,lock tables,replication client,process on *.* to backup@'%' identified by 'password';
grant replication slave,replication client on *.* to repl@'%' identified by 'fpassword';

主库和从库上分别安装xtrabackup

https://www.percona.com/downloads/Percona-XtraBackup-2.4/LATEST/

https://www.percona.com/redir/downloads/percona-release/redhat

https://www.percona.com/downloads/Percona-XtraBackup-2.4/Percona-XtraBackup-2.4.18/binary/redhat/7/x86_64/percona-xtrabackup-24-2.4.18-1.el7.x86_64.rpm

yum install epel-release
yum install https://www.percona.com/redir/downloads/percona-release/redhat/1.0-14/percona-release-1.0-14.noarch.rpm
yum install libev qpress
yum install perl-DBD-MySQL
yum install percona-xtrabackup-24

主、从库分别建备份目录

mkdir -p /data/backups/

主库上发起流备份，并通过管道传输到从库解包

xtrabackup -ubackup -ppassword -H127.0.0.1 -P3306 \
--backup \
--stream=xbstream \
--compress \
--target-dir=/data/backups/ | ssh root@192.168.199.199 "xbstream -x -C /data/backups"

从库上解压，解压后删除原压缩文件

xtrabackup --decompress --parallel=4 --remove-original --target-dir=/data/backups/

从库上prepare阶段，应用redo log

xtrabackup --prepare --use-memory=1GB --target-dir=/data/backups/

从库采用move-back方法，把应用好的数据恢复到数据目录

xtrabackup --defaults-file=/data/mysql/my.cnf --move-back --parallel=4 --target-dir=/data/backups/

注意:这里有一个坑，不要设置innodb_log_group_home_dir =./ ，xtrabackup会读错路径，导致无法拷贝，解决办法是注释掉这条参数。

从库修改数据目录权限

chown -R mysql:mysql /database/mysql/

从库修改gtid编号

cat /data/mysql/mysql3306/data/xtrabackup_info |grep binlog_pos
binlog_pos = filename 'mysql-bin.000009', position '190', GTID of the last change 'c0900221-709b-11e9-b8ea-000c29abbade:1-1539006'

mysql>  reset master;
mysql>  set global gtid_purged="c0900221-709b-11e9-b8ea-000c29abbade:1-1539006"

从库启动复制

mysql> CHANGE MASTER TO
       MASTER_HOST='192.168.199.198',
       MASTER_USER='repl',
       MASTER_PASSWORD='fanderpassword',
       MASTER_PORT=3306,
       MASTER_AUTO_POSITION=1;

mysql> start slave;