最近系统漏洞扫描，扫出来很多MySQL的漏洞，没有什么好的办法，先升级到最新版本。在梳理MySQL数据库信息时发现有一套zabbix用的MySQL版本是5.1.71的，现在的最新版本是5.7.17，版本跨越的太大了，不知道直接升级是否可行。库的数据量大概15G，于是就想先备份，备份完后用mysql_upgrade做升级。如果实在不行就再新创建一套库把数据导进去。
下面是在虚拟机上测试的升级步骤，中间也遇到了一些问题，不过好在最后还是升级成功了，说明这条路还是可行了。
操作系统版本RHEL 6.7 旧的MySQL版本5.1.71，新的MySQL版本5.7.17。
1、查看旧的MySQL版本，并创建测试数据库和测试表
mysql> select version();
+------------------+
| version() |
+------------------+
| 5.1.71-community |
+------------------+
mysql> create database zx;
Query OK, 1 row affected (0.00 sec)
mysql> show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
| mysql |
| test |
| zx |
+--------------------+
4 rows in set (0.00 sec)
mysql> use zx;
Database changed
mysql> create table test_upgrade (id int);
Query OK, 0 rows affected (0.07 sec)
......
mysql> select count(*) from test_upgrade;
+----------+
| count(*) |
+----------+
| 33554432 |
+----------+
1 row in set (0.00 sec)
现在test_upgrade表里有33554432条数据。
2、停止旧MySQL，并备份数据
[root@rhel6 mysql]# service mysql stop
Shutting down MySQL.. SUCCESS!
#这里直接用cp备份数据
[root@rhel6 lib]# cp -R mysql mysql_bak
[root@rhel6 lib]# du -sk mysql*
250880 mysql
250880 mysql_bak
3、安装新Msql软件，这里下载的是编译好的解压就可以使用
[root@rhel6 ~]# tar -zxvf mysql-5.7.17-linux-glibc2.5-x86_64.tar.gz
#解压完后移动到/opt目录下
[root@rhel6 ~]# mv mysql-5.7.17-linux-glibc2.5-x86_64 mysql-5.7.17
[root@rhel6 ~]# mv mysql-5.7.17 /opt
[root@rhel6 ~]# cd /opt
[root@rhel6 opt]# chown -R mysql:mysql mysql-5.7.17/
[root@rhel6 opt]# ll
total 4
drwxr-xr-x. 9 mysql mysql 4096 Mar 22 21:07 mysql-5.7.17
4、修改my.cnf
主要修改basedir参数：
[root@rhel6 opt]# vi /etc/my.cnf
basedir=/opt/mysql-5.7.17
5、启动新MySQL
[root@rhel6 mysql-5.7.17]# ./bin/mysqld_safe &
1)启动报错1：
2017-03-22T13:12:39.131998Z 0 [ERROR] InnoDB: The Auto-extending innodb_system data file './ibdata1' is of a different size 640 pages (rounded down to MB) than specified in the .cnf file: initial 768 pages, max 0 (relevant if non-zero) pages!2017-03-22T13:12:39.132028Z 0 [ERROR] InnoDB: Plugin initialization aborted with error Generic error
2017-03-22T13:12:39.733953Z 0 [ERROR] Plugin 'InnoDB' init function returned error.
2017-03-22T13:12:39.733986Z 0 [ERROR] Plugin 'InnoDB' registration as a STORAGE ENGINE failed.
2017-03-22T13:12:39.733994Z 0 [ERROR] Failed to initialize plugins.
2017-03-22T13:12:39.734000Z 0 [ERROR] Aborting
解决方法在my.cnf中的[mysqld]部分添加如下参数
innodb_data_file_path = ibdata1:10M:autoextend
再次启动
2)启动报错2：
2017-03-22T13:16:03.374717Z 0 [ERROR] unknown option '--skip-locking'
2017-03-22T13:16:03.374735Z 0 [ERROR] Aborting
解决方法从my.cnf中注释掉相关参数skip-locking
再次启动
3)启动报错3：
2017-03-22T13:18:20.278752Z 0 [ERROR] Fatal error: mysql.user table is damaged. Please run mysql_upgrade.
2017-03-22T13:18:20.278954Z 0 [ERROR] Aborting
5.7无法读取5.1的mysql.user表，解决方法使用--skip-grant-tables参数跳过授权验证
再次启动
[root@rhel6 mysql-5.7.17]# ./bin/mysqld_safe --skip-grant-tables&
启动成功
2017-03-22T13:20:23.919677Z 0 [Note] ./bin/mysqld: ready for connections.
Version: '5.7.17' socket: '/var/lib/mysql/mysql.sock' port: 3306 MySQL Community Server (GPL)
6、执行升级
[root@rhel6 mysql-5.7.17]# ./bin/mysql_upgrade -uroot
Checking if update is needed.
Checking server version.
Running queries to upgrade MySQL server.
Checking system database.
mysql.columns_priv OK
mysql.db OK
mysql.engine_cost OK
mysql.event OK
mysql.func OK
mysql.general_log OK
mysql.gtid_executed OK
mysql.help_category OK
mysql.help_keyword OK
mysql.help_relation OK
mysql.help_topic OK
mysql.host OK
mysql.innodb_index_stats OK
mysql.innodb_table_stats OK
mysql.ndb_binlog_index OK
mysql.plugin OK
mysql.proc OK
mysql.procs_priv OK
mysql.proxies_priv OK
mysql.server_cost OK
mysql.servers OK
mysql.slave_master_info OK
mysql.slave_relay_log_info OK
mysql.slave_worker_info OK
mysql.slow_log OK
mysql.tables_priv OK
mysql.time_zone OK
mysql.time_zone_leap_second OK
mysql.time_zone_name OK
mysql.time_zone_transition OK
mysql.time_zone_transition_type OK
mysql.user OK
Upgrading the sys schema.
Checking databases.
sys.sys_config OK
zx.test_upgrade OK
Upgrade process completed successfully.
Checking if update is needed.
7、重启MySQL，并验证