mysqlbinlog恢复bin-log数据
Binlog日志即binary log,是二进制日志文件,有两个作用,一个是增量备份,另一个是主从复制,即从节点同步主节点数据时获取的即是bin-log,也可以通过bin-log日志来进行本机数据恢复。
1、可以登录mysql客户端查看bin-log有没有开启:
mysql> show variables like '%log_bin%';
+---------------------------------+--------------------------------+
| Variable_name | Value |
+---------------------------------+--------------------------------+
| log_bin | ON |
| log_bin_basename | /var/lib/mysql/mysql-bin |
| log_bin_index | /var/lib/mysql/mysql-bin.index |
| log_bin_trust_function_creators | OFF |
| log_bin_use_v1_row_events | OFF |
| sql_log_bin | ON |
+---------------------------------+--------------------------------+
6 rows in set (0.02 sec)
log_bin为ON时,binlog即开启,为OFF,未开启。以上已开启
2、开启mysql binlog日志:
进入mysql主配置文件(vim /etc/my.cnf),在mysqld模块下增加以下参数
server-id = 1(单个节点id)
log-bin= /var/lib/mysql/mysql-bin(位置一般和mysql库文件所在位置一样)
expire_logs_days = 10(表示此日志保存时间为10天;在mysql 8的版本中已经不建议使用此参数)
3、binlog日志包括两类文件;第一个是二进制索引文件(后缀为.index),第二个为日志文件(后缀名称为.0000*),记录所有的DML(除SELECT)及DDL语句事件
[root@TestCentos7 ~]# ls /var/lib/mysql/
mysql-bin.000001 mysql-bin.000002 mysql-bin.index mysql.sock
4、查看binlog日志列表:show master logs;
mysql> show master logs;
+------------------+-----------+-----------+
| Log_name | File_size | Encrypted |
+------------------+-----------+-----------+
| mysql-bin.000001 | 2412 | No |
| mysql-bin.000002 | 445 | No |
+------------------+-----------+-----------+
2 rows in set (0.00 sec)
5、查看最后一个binlog日志的编号名称及其最后一个操作事件pos结束点的值:show master status;
mysql> show master status;
+------------------+----------+--------------+------------------+----------------------------------------+
| File | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set |
+------------------+----------+--------------+------------------+----------------------------------------+
| mysql-bin.000002 | 445 | | | c9fba9e2-db3b-11eb-81d4-000c298d8da1:1 |
+------------------+----------+--------------+------------------+----------------------------------------+
1 row in set (0.00 sec)
注意:如果mysql没有开启GTID的话,不会有pos结束点的值,可以使用 show variables like '%gtid_mode%'; 检查是否开启。
6、flush logs 刷新日志,生成一个新编号的binlog文件:
mysql> flush logs;
Query OK, 0 rows affected (0.00 sec)
mysql> show master logs;
+------------------+-----------+-----------+
| Log_name | File_size | Encrypted |
+------------------+-----------+-----------+
| mysql-bin.000001 | 2412 | No |
| mysql-bin.000002 | 492 | No |
| mysql-bin.000003 | 195 | No |
+------------------+-----------+-----------+
3 rows in set (0.00 sec)
每当mysqld服务重启后,会自动刷新binlog文件,mysqldump数据时也可以加-F选项来刷新binlog日志文件
7、清空所有binlog日志文件用 reset master;
8、查看binlog文件内容,使用查看工具mysqlbinlog来查看(vi/vim/cat等都打不开)
# mysqlbinlog mysql-bin.000002 | more
BEGIN
/*!*/;
# at 309
#201123 14:16:09 server id 100 end_log_pos 369 CRC32 0x73d92352 Table_map: `vfan`.`student` mapped to number 86
# at 369
#201123 14:16:09 server id 100 end_log_pos 414 CRC32 0x0e056855 Write_rows: table id 86 flags: STMT_END_F
BINLOG '
qVO7XxNkAAAAPAAAAHEBAAAAAFYAAAAAAAEABHZmYW4AB3N0dWRlbnQAAwMPAQI8AAABAYACASFS
I9lz
qVO7Xx5kAAAALQAAAJ4BAAAAAFYAAAAAAAEAAgAD/wAFAAAAA0hlZxNVaAUO
'/*!*/;
# at 414
#201123 14:16:09 server id 100 end_log_pos 445 CRC32 0xfaf4f9c6 Xid = 10
COMMIT/*!*/;
# at 445
#201123 14:19:20 server id 100 end_log_pos 492 CRC32 0x95a77234 Rotate to mysql-bin.000003 pos: 4
14:16:09 —— 时间
server id 100 —— server id(my.cnf中设置的id)
end_log_pos 492 —— 结束的Pos点
9、上边的方法内容比较多,也不太容易观察,以下命令更方便查看:show binlog events in 'mysql-bin.000002';
mysql> show binlog events in 'mysql-bin.000002';
+------------------+-----+----------------+-----------+-------------+-------------------------------------------------------------------+
| Log_name | Pos | Event_type | Server_id | End_log_pos | Info |
+------------------+-----+----------------+-----------+-------------+-------------------------------------------------------------------+
| mysql-bin.000002 | 4 | Format_desc | 100 | 124 | Server ver: 8.0.16, Binlog ver: 4 |
| mysql-bin.000002 | 124 | Previous_gtids | 100 | 155 | |
| mysql-bin.000002 | 155 | Gtid | 100 | 234 | SET @@SESSION.GTID_NEXT= 'c9fba9e2-db3b-11eb-81d4-000c298d8da1:1' |
| mysql-bin.000002 | 234 | Query | 100 | 309 | BEGIN |
| mysql-bin.000002 | 309 | Table_map | 100 | 369 | table_id: 86 (vfan.student) |
| mysql-bin.000002 | 369 | Write_rows | 100 | 414 | table_id: 86 flags: STMT_END_F |
| mysql-bin.000002 | 414 | Xid | 100 | 445 | COMMIT /* xid=10 */ |
| mysql-bin.000002 | 445 | Rotate | 100 | 492 | mysql-bin.000003;pos=4 |
+------------------+-----+----------------+-----------+-------------+-------------------------------------------------------------------+
8 rows in set (0.00 sec)
10、指定查询
(1)从Pos点414开始查询,如下:
mysql> show binlog events in 'mysql-bin.000002' from 414;
+------------------+-----+------------+-----------+-------------+------------------------+
| Log_name | Pos | Event_type | Server_id | End_log_pos | Info |
+------------------+-----+------------+-----------+-------------+------------------------+
| mysql-bin.000002 | 414 | Xid | 100 | 445 | COMMIT /* xid=10 */ |
| mysql-bin.000002 | 445 | Rotate | 100 | 492 | mysql-bin.000003;pos=4 |
+------------------+-----+------------+-----------+-------------+------------------------+
2 rows in set (0.00 sec)
(2)从Pos点155开始查询,跳过中间两行,查询后4条数据
mysql> show binlog events in 'mysql-bin.000002' from 155 limit 2,4;
+------------------+-----+------------+-----------+-------------+--------------------------------+
| Log_name | Pos | Event_type | Server_id | End_log_pos | Info |
+------------------+-----+------------+-----------+-------------+--------------------------------+
| mysql-bin.000002 | 309 | Table_map | 100 | 369 | table_id: 86 (vfan.student) |
| mysql-bin.000002 | 369 | Write_rows | 100 | 414 | table_id: 86 flags: STMT_END_F |
| mysql-bin.000002 | 414 | Xid | 100 | 445 | COMMIT /* xid=10 */ |
| mysql-bin.000002 | 445 | Rotate | 100 | 492 | mysql-bin.000003;pos=4 |
+------------------+-----+------------+-----------+-------------+--------------------------------+
(3)从Pos点155开始查询后四行
mysql> show binlog events in 'mysql-bin.000002' from 155 limit 4;
+------------------+-----+------------+-----------+-------------+-------------------------------------------------------------------+
| Log_name | Pos | Event_type | Server_id | End_log_pos | Info |
+------------------+-----+------------+-----------+-------------+-------------------------------------------------------------------+
| mysql-bin.000002 | 155 | Gtid | 100 | 234 | SET @@SESSION.GTID_NEXT= 'c9fba9e2-db3b-11eb-81d4-000c298d8da1:1' |
| mysql-bin.000002 | 234 | Query | 100 | 309 | BEGIN |
| mysql-bin.000002 | 309 | Table_map | 100 | 369 | table_id: 86 (vfan.student) |
| mysql-bin.000002 | 369 | Write_rows | 100 | 414 | table_id: 86 flags: STMT_END_F |
+------------------+-----+------------+-----------+-------------+-------------------------------------------------------------------+
4 rows in set (0.00 sec)
11、利用bin-log日志恢复mysql数据,现在有一张表student如下:
mysql> select * from student;
+----+------+-----+
| id | name | age |
+----+------+-----+
| 1 | Tony | 18 |
| 2 | Any | 17 |
| 3 | Goy | 20 |
| 4 | Baly | 18 |
| 5 | Heg | 19 |
+----+------+-----+
5 rows in set (0.00 sec)
(1)先模拟全量备份,进行mysqldump备份
[root@TestCentos7 data]# mysqldump -uroot -proot1 vfan > dump1.sql
(2)由于业务需要,需要对此表进行插入(6 和 7)
mysql> select * from student;
+----+------+-----+
| id | name | age |
+----+------+-----+
| 1 | Tony | 18 |
| 2 | Any | 17 |
| 3 | Goy | 20 |
| 4 | Baly | 18 |
| 5 | Heg | 19 |
| 6 | Mom | 20 |
| 7 | Lei | 21 |
+----+------+-----+
7 rows in set (0.00 sec)
(3)由于业务需要,要将id=3的name更改为Giil
mysql> UPDATE student set name='Giil' where id=3;
Query OK, 1 row affected (0.00 sec)
Rows matched: 1 Changed: 1 Warnings: 0
mysql> select * from student;
+----+------+-----+
| id | name | age |
+----+------+-----+
| 1 | Tony | 18 |
| 2 | Any | 17 |
| 3 | Giil | 20 |
| 4 | Baly | 18 |
| 5 | Heg | 19 |
| 6 | Mom | 20 |
| 7 | Lei | 21 |
+----+------+-----+
7 rows in set (0.01 sec)
(4)操作失误,勿将 vfan 数据库删除
mysql> drop database vfan;
Query OK, 1 row affected (0.10 sec)
(5)先进行全量恢复一下:
mysql> CREATE DATABASE vfan;
mysql> use vfan
Database changed
mysql> source /data/dump1.sql
mysql> select * from student;
+----+------+-----+
| id | name | age |
+----+------+-----+
| 1 | Tony | 18 |
| 2 | Any | 17 |
| 3 | Goy | 20 |
| 4 | Baly | 18 |
| 5 | Heg | 19 |
+----+------+-----+
5 rows in set (0.00 sec)
然后通过binlog进行增量恢复,先flush logs;一下,防止再有操作写进此binlog日志中,会增加恢复难度:
mysql> flush logs;
Query OK, 0 rows affected (0.01 sec)
mysql> show master logs;
+------------------+-----------+-----------+
| Log_name | File_size | Encrypted |
+------------------+-----------+-----------+
| mysql-bin.000001 | 2412 | No |
| mysql-bin.000002 | 492 | No |
| mysql-bin.000003 | 1219 | No |
| mysql-bin.000004 | 195 | No |
+------------------+-----------+-----------+
4 rows in set (0.00 sec)
查看mysql-bin.000003的具体信息,如下:
INSERT操作:事务的起始Pos点为274,事务提交结束点为495
UPDATE操作:事务的起始Pos点为574,事务提交结束点为886
(6)开始恢复INSERT的数据,执行:
mysqlbinlog --start-position=274 --stop-position=495 --database=vfan /var/lib/mysql/mysql-bin.000003 | mysql -uroot -proot1 -v vfan
此命令意思为mysqlbinlog读取binlog日志内容并通过管道符传给mysql命令,-v表示执行此mysql命令
我执行后有一个报错,大概是GTID_MODE的参数错误:
# mysqlbinlog --start-position=274 --stop-position=495 --database=vfan /var/lib/mysql/mysql-bin.000003 | /mysql -uroot -proot1 -v vfan
ERROR 1782 (HY000) at line 23: @@SESSION.GTID_NEXT cannot be set to ANONYMOUS when @@GLOBAL.GTID_MODE = ON.
只需将gtid_mode设置为OFF_PERMISSIVE即可
mysql> set global gtid_mode='on_permissive';
Query OK, 0 rows affected (0.01 sec)
mysql> set global gtid_mode='off_permissive';
Query OK, 0 rows affected (0.12 sec)
mysql> show variables like '%gtid_mode%';
+---------------+----------------+
| Variable_name | Value |
+---------------+----------------+
| gtid_mode | OFF_PERMISSIVE |
+---------------+----------------+
1 row in set (0.00 sec)
再重新执行以上mysqlbinlog命令,执行成功!
再次查看student表内数据:
mysql> select * from student ;
+----+------+-----+
| id | name | age |
+----+------+-----+
| 1 | Tony | 18 |
| 2 | Any | 17 |
| 3 | Goy | 20 |
| 4 | Baly | 18 |
| 5 | Heg | 19 |
| 6 | Mom | 20 |
| 7 | Lei | 21 |
+----+------+-----+
7 rows in set (0.00 sec)
INSERT操作的数据已经恢复
(7)开始恢复UPDATE的数据
/usr/local/mysql/bin/mysqlbinlog --start-position=574 --stop-position=886 --database=vfan /var/lib/mysql/mysql-bin.000003 | /usr/local/mysql/bin/mysql -uroot -proot1 -v vfan
再次查看,UPDATE的数据也已经恢复:
mysql> select * from student ;
+----+------+-----+
| id | name | age |
+----+------+-----+
| 1 | Tony | 18 |
| 2 | Any | 17 |
| 3 | Giil | 20 |
| 4 | Baly | 18 |
| 5 | Heg | 19 |
| 6 | Mom | 20 |
| 7 | Lei | 21 |
+----+------+-----+
7 rows in set (0.00 sec)
12、还有另一种可以通过时间来进行恢复:
还是将数据库误删,然后全量恢复完毕,准备增量恢复。
mysql> select * from student;
+----+------+-----+
| id | name | age |
+----+------+-----+
| 1 | Tony | 18 |
| 2 | Any | 17 |
| 3 | Goy | 20 |
| 4 | Baly | 18 |
| 5 | Heg | 19 |
+----+------+-----+
5 rows in set (0.00 sec)
(1)先使用mysqlbinlog查看操作时间
mysqlbinlog mysql-bin.000003 | more
(2)开始恢复,直接将INSERT和UPDATE数据一并恢复
mysqlbinlog --start-datetime="2020-11-23 14:44:18" --stop-datetime="2020-11-23 14:46:28" --database=vfan /var/lib/mysql/mysql-bin.000003 | mysql -uroot -proot1 -v vfan