mysql主备切换canal出现的问题解析
通过配置VIP，在进行主备切换时，出现的报错信息：
1.当主备节点当前binlog文件名称相同时，原主节点的position小于主备切换后的position，出现如下报错：
2020-07-02 15:08:09,332 INFO [destination = 1-236 , address = /192.168.3.100:3306 , EventParser] MysqlConnection:293 | Register slave RegisterSlaveCommandPacket[reportHost=192.168.3.1,reportPort=63292,reportUser=canal_repl_user,reportPasswd=111111,serverId=10236,command=21]
2020-07-02 15:08:21,227 INFO [destination = 1-236 , address = /192.168.3.100:3306 , EventParser] MysqlConnection:321 | COM_BINLOG_DUMP with position:BinlogDumpCommandPacket[binlogPosition=1104,slaveServerId=10236,binlogFileName=mysql-bin.000002,command=18]
2020-07-02 15:08:24,979 INFO [destination = 1-236 , address = /192.168.3.100:3306 , EventParser] LogEvent:122 | common_header_len= 19, number_of_event_types= 38
2020-07-02 15:08:24,983 ERROR [destination = 1-236 , address = /192.168.3.100:3306 , EventParser] DirectLogFetcher:163 | I/O error while reading from client socket
java.io.IOException: Received error packet: errno = 1236, sqlstate = HY000 errmsg = log event entry exceeded max_allowed_packet; Increase max_allowed_packet on master; the first event 'mysql-bin.000002' at 1104, the last event read from '/usr/local/mysql/logs/mysql-bin.000002' at 123, the last byte read from '/usr/local/mysql/logs/mysql-bin.000002' at 1123.
at com.alibaba.otter.canal.parse.inbound.mysql.dbsync.DirectLogFetcher.fetch(DirectLogFetcher.java:102)
at com.alibaba.otter.canal.parse.inbound.mysql.MysqlConnection.dump(MysqlConnection.java:169)
at com.alibaba.otter.canal.parse.inbound.AbstractEventParser$3.run(AbstractEventParser.java:279)
at java.lang.Thread.run(Thread.java:748)
2020-07-02 15:08:24,989 ERROR [destination = 1-236 , address = /192.168.3.100:3306 , EventParser] MysqlEventParser:301 | dump address 192.168.3.100/192.168.3.100:3306 has an error, retrying. caused by
java.io.IOException: Received error packet: errno = 1236, sqlstate = HY000 errmsg = log event entry exceeded max_allowed_packet; Increase max_allowed_packet on master; the first event 'mysql-bin.000002' at 1104, the last event read from '/usr/local/mysql/logs/mysql-bin.000002' at 123, the last byte read from '/usr/local/mysql/logs/mysql-bin.000002' at 1123.
at com.alibaba.otter.canal.parse.inbound.mysql.dbsync.DirectLogFetcher.fetch(DirectLogFetcher.java:102)
at com.alibaba.otter.canal.parse.inbound.mysql.MysqlConnection.dump(MysqlConnection.java:169)
at com.alibaba.otter.canal.parse.inbound.AbstractEventParser$3.run(AbstractEventParser.java:279)
at java.lang.Thread.run(Thread.java:748)
2020-07-02 15:08:24,994 ERROR [destination = 1-236 , address = /192.168.3.100:3306 , EventParser] LogAlarmHandler:19 | destination:1-236[java.io.IOException: Received error packet: errno = 1236, sqlstate = HY000 errmsg = log event entry exceeded max_allowed_packet; Increase max_allowed_packet on master; the first event 'mysql-bin.000002' at 1104, the last event read from '/usr/local/mysql/logs/mysql-bin.000002' at 123, the last byte read from '/usr/local/mysql/logs/mysql-bin.000002' at 1123.
at com.alibaba.otter.canal.parse.inbound.mysql.dbsync.DirectLogFetcher.fetch(DirectLogFetcher.java:102)
at com.alibaba.otter.canal.parse.inbound.mysql.MysqlConnection.dump(MysqlConnection.java:169)
at com.alibaba.otter.canal.parse.inbound.AbstractEventParser$3.run(AbstractEventParser.java:279)
at java.lang.Thread.run(Thread.java:748)
]
此类报错和max_allowed_packet相关。首先max_allowed_packet控制着主从复制过程中单个语句产生的二进制binlog event大小，它的值必须是1024的倍数 。出现此类错误的常见原因：
1>.该参数在主备库的配置大小不一致。 从主库传递到备库的binlog event大小超过了主库或者备库的max_allowed_packet大小。可以查看变量值：SHOW GLOBAL VARIABLES LIKE "%max_allowed_packet%"; 看两个库的值是否一致。
2>.在对应个binlog文件中找不到对应的偏移量position，可以通过mysqlbinlog命令查看，发现没有要报错要找的1104(position)，可以切换到存在的position位点
mysqlbinlog mysql-bin.000002 --stop-position=1200 /*!50530 SET @@SESSION.PSEUDO_SLAVE_MODE=1*/;
/*!50003 SET @OLD_COMPLETION_TYPE=@@COMPLETION_TYPE,COMPLETION_TYPE=0*/;
DELIMITER /*!*/;
# at 4
#200630 16:24:37 server id 2 end_log_pos 123 CRC32 0x87e4bed6 Start: binlog v 4, server v 5.7.28-log created 200630 16:24:37
# Warning: this binlog is either in use or was not closed properly.
BINLOG '
xfb6Xg8CAAAAdwAAAHsAAAABAAQANS43LjI4LWxvZwAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
AAAAAAAAAAAAAAAAAAAAAAAAEzgNAAgAEgAEBAQEEgAAXwAEGggAAAAICAgCAAAACgoKKioAEjQA
Ada+5Ic=
'/*!*/;
# at 123
#200630 16:24:37 server id 2 end_log_pos 234 CRC32 0xd95db8f4 Previous-GTIDs
# b3a0925e-b78b-11ea-9b67-000c2915fd70:51-55,
# b85582c3-14d9-11ea-a64a-000c29ab1835:40-52
# at 234
#200630 16:25:23 server id 1 end_log_pos 299 CRC32 0x0ed285db GTID last_committed=0 sequence_number=1 rbr_only=yes
/*!50718 SET TRANSACTION ISOLATION LEVEL READ COMMITTED*//*!*/;
SET @@SESSION.GTID_NEXT= 'b85582c3-14d9-11ea-a64a-000c29ab1835:53'/*!*/;
# at 299
#200630 16:25:23 server id 1 end_log_pos 362 CRC32 0x34ec0ffb Query thread_id=11 exec_time=0 error_code=0
SET TIMESTAMP=1593505523/*!*/;
SET @@session.pseudo_thread_id=11/*!*/;
SET @@session.foreign_key_checks=1, @@session.sql_auto_is_null=0, @@session.unique_checks=1, @@session.autocommit=1/*!*/;
SET @@session.sql_mode=524288/*!*/;
SET @@session.auto_increment_increment=1, @@session.auto_increment_offset=1/*!*/;
/*!\C utf8 *//*!*/;
SET @@session.character_set_client=33,@@session.collation_connection=33,@@session.collation_server=33/*!*/;
SET @@session.lc_time_names=0/*!*/;
SET @@session.collation_database=DEFAULT/*!*/;
BEGIN
/*!*/;
# at 362
#200630 16:25:23 server id 1 end_log_pos 427 CRC32 0x62a09b2f Table_map: `test`.`test_canal_2_hive` mapped to number 114
# at 427
#200630 16:25:23 server id 1 end_log_pos 492 CRC32 0x0f349879 Write_rows: table id 114 flags: STMT_END_F BINLOG '
8/b6XhMBAAAAQQAAAKsBAAAAAHIAAAAAAAEABHRlc3QAEXRlc3RfY2FuYWxfMl9oaXZlAAMIDxED
UAAABi+boGI=
8/b6Xh4BAAAAQQAAAOwBAAAAAHIAAAAAAAEAAgAD//iYAAAAAAAAABB6aGFuZ3Nhbi0wMS1zMTI5
Xvr283mYNA8=
'/*!*/;
# at 492
#200630 16:25:23 server id 1 end_log_pos 523 CRC32 0x9d38dbb3 Xid = 542
COMMIT/*!*/;
# at 523
#200630 16:31:33 server id 1 end_log_pos 588 CRC32 0x7a71df00 GTID last_committed=1 sequence_number=2 rbr_only=yes
/*!50718 SET TRANSACTION ISOLATION LEVEL READ COMMITTED*//*!*/;
SET @@SESSION.GTID_NEXT= 'b85582c3-14d9-11ea-a64a-000c29ab1835:54'/*!*/;
# at 588
#200630 16:31:33 server id 1 end_log_pos 651 CRC32 0xec353d4a Query thread_id=11 exec_time=0 error_code=0
SET TIMESTAMP=1593505893/*!*/;
BEGIN
/*!*/;
# at 651
#200630 16:31:33 server id 1 end_log_pos 716 CRC32 0x0309e1d5 Table_map: `test`.`test_canal_2_hive` mapped to number 114
# at 716
#200630 16:31:33 server id 1 end_log_pos 781 CRC32 0xb7ac4767 Write_rows: table id 114 flags: STMT_END_F BINLOG '
Zfj6XhMBAAAAQQAAAMwCAAAAAHIAAAAAAAEABHRlc3QAEXRlc3RfY2FuYWxfMl9oaXZlAAMIDxED
UAAABtXhCQM=
Zfj6Xh4BAAAAQQAAAA0DAAAAAHIAAAAAAAEAAgAD//iZAAAAAAAAABB6aGFuZ3Nhbi0wMS1zMTI5
Xvr4ZWdHrLc=
'/*!*/;
# at 781
#200630 16:31:33 server id 1 end_log_pos 812 CRC32 0xa8c3ce12 Xid = 550
COMMIT/*!*/;
# at 812
#200630 16:52:25 server id 1 end_log_pos 877 CRC32 0x8e7366ee GTID last_committed=2 sequence_number=3 rbr_only=no
SET @@SESSION.GTID_NEXT= 'b85582c3-14d9-11ea-a64a-000c29ab1835:55'/*!*/;
# at 877
#200630 16:52:25 server id 1 end_log_pos 1122 CRC32 0xb5c35333 Query thread_id=11 exec_time=0 error_code=0
use `test`/*!*/;
SET TIMESTAMP=1593507145/*!*/;
SET @@session.sql_mode=1436549152/*!*/;
GRANT REPLICATION SLAVE, REPLICATION CLIENT ON *.* TO 'canal_repl_user'@'%' IDENTIFIED WITH 'mysql_native_password' AS '*FD571203974BA9AFE270FE62151AE967ECA5E0AA'
/*!*/;
# at 1122
#200630 16:52:29 server id 1 end_log_pos 1187 CRC32 0x2f039a0c GTID last_committed=3 sequence_number=4 rbr_only=no
SET @@SESSION.GTID_NEXT= 'b85582c3-14d9-11ea-a64a-000c29ab1835:56'/*!*/;
# at 1187
#200630 16:52:29 server id 1 end_log_pos 1278 CRC32 0x0348011d Query thread_id=11 exec_time=0 error_code=0
SET TIMESTAMP=1593507149/*!*/;
SET @@session.time_zone='SYSTEM'/*!*/;
flush privileges
/*!*/;
SET @@SESSION.GTID_NEXT= 'AUTOMATIC' /* added by mysqlbinlog */ /*!*/;
DELIMITER ;
# End of log file
/*!50003 SET COMPLETION_TYPE=@OLD_COMPLETION_TYPE*/;
/*!50530 SET @@SESSION.PSEUDO_SLAVE_MODE=0*/;
2.当mysql主备切换时，无论binlog文件名是否相同，如果原主节点position大于主备切换后主库当前binlog的position，会报如下错误：
2020-07-02 14:51:16,671 INFO [destination = 1-236 , address = /192.168.3.100:3306 , EventParser] MysqlConnection:293 | Register slave RegisterSlaveCommandPacket[reportHost=192.168.3.1,reportPort=60838,reportUser=canal_repl_user,reportPasswd=111111,serverId=10236,command=21]
2020-07-02 14:51:16,671 INFO [destination = 1-236 , address = /192.168.3.100:3306 , EventParser] MysqlConnection:321 | COM_BINLOG_DUMP with position:BinlogDumpCommandPacket[binlogPosition=10262,slaveServerId=10236,binlogFileName=mysql-bin.000002,command=18]
2020-07-02 14:51:16,672 ERROR [destination = 1-236 , address = /192.168.3.100:3306 , EventParser] DirectLogFetcher:163 | I/O error while reading from client socket
java.io.IOException: Received error packet: errno = 1236, sqlstate = HY000 errmsg = Client requested master to start replication from position > file size
at com.alibaba.otter.canal.parse.inbound.mysql.dbsync.DirectLogFetcher.fetch(DirectLogFetcher.java:102)
at com.alibaba.otter.canal.parse.inbound.mysql.MysqlConnection.dump(MysqlConnection.java:169)
at com.alibaba.otter.canal.parse.inbound.AbstractEventParser$3.run(AbstractEventParser.java:279)
at java.lang.Thread.run(Thread.java:748)
2020-07-02 14:51:16,673 ERROR [destination = 1-236 , address = /192.168.3.100:3306 , EventParser] MysqlEventParser:301 | dump address 192.168.3.100/192.168.3.100:3306 has an error, retrying. caused by
java.io.IOException: Received error packet: errno = 1236, sqlstate = HY000 errmsg = Client requested master to start replication from position > file size
at com.alibaba.otter.canal.parse.inbound.mysql.dbsync.DirectLogFetcher.fetch(DirectLogFetcher.java:102)
at com.alibaba.otter.canal.parse.inbound.mysql.MysqlConnection.dump(MysqlConnection.java:169)
at com.alibaba.otter.canal.parse.inbound.AbstractEventParser$3.run(AbstractEventParser.java:279)
at java.lang.Thread.run(Thread.java:748)
2020-07-02 14:51:16,769 ERROR [destination = 1-236 , address = /192.168.3.100:3306 , EventParser] LogAlarmHandler:19 | destination:1-236[java.io.IOException: Received error packet: errno = 1236, sqlstate = HY000 errmsg = Client requested master to start replication from position > file size
at com.alibaba.otter.canal.parse.inbound.mysql.dbsync.DirectLogFetcher.fetch(DirectLogFetcher.java:102)
at com.alibaba.otter.canal.parse.inbound.mysql.MysqlConnection.dump(MysqlConnection.java:169)
at com.alibaba.otter.canal.parse.inbound.AbstractEventParser$3.run(AbstractEventParser.java:279)
at java.lang.Thread.run(Thread.java:748)
]
从错误信息可以看出，复制时其实position大于当前binlog文件的大小
3.mysql主备切换时，原主库binlog名称序号大于切换后主库binlog名称序号，会报如下错误：
2020-07-06 11:35:07,977 INFO [destination = 1-236 , address = /192.168.3.100:3306 , EventParser] MysqlConnection:293 | Register slave RegisterSlaveCommandPacket[reportHost=192.168.3.1,reportPort=59469,reportUser=canal_repl_user,reportPasswd=111111,serverId=10236,command=21]
2020-07-06 11:35:07,978 INFO [destination = 1-236 , address = /192.168.3.100:3306 , EventParser] MysqlConnection:321 | COM_BINLOG_DUMP with position:BinlogDumpCommandPacket[binlogPosition=1411,slaveServerId=10236,binlogFileName=mysql-bin.000003,command=18]
2020-07-06 11:35:07,979 ERROR [destination = 1-236 , address = /192.168.3.100:3306 , EventParser] DirectLogFetcher:163 | I/O error while reading from client socket
java.io.IOException: Received error packet: errno = 1236, sqlstate = HY000 errmsg = Could not find first log file name in binary log index file
at com.alibaba.otter.canal.parse.inbound.mysql.dbsync.DirectLogFetcher.fetch(DirectLogFetcher.java:102)
at com.alibaba.otter.canal.parse.inbound.mysql.MysqlConnection.dump(MysqlConnection.java:169)
at com.alibaba.otter.canal.parse.inbound.AbstractEventParser$3.run(AbstractEventParser.java:279)
at java.lang.Thread.run(Thread.java:748)
2020-07-06 11:35:07,980 ERROR [destination = 1-236 , address = /192.168.3.100:3306 , EventParser] MysqlEventParser:301 | dump address 192.168.3.100/192.168.3.100:3306 has an error, retrying. caused by
java.io.IOException: Received error packet: errno = 1236, sqlstate = HY000 errmsg = Could not find first log file name in binary log index file
at com.alibaba.otter.canal.parse.inbound.mysql.dbsync.DirectLogFetcher.fetch(DirectLogFetcher.java:102)
at com.alibaba.otter.canal.parse.inbound.mysql.MysqlConnection.dump(MysqlConnection.java:169)
at com.alibaba.otter.canal.parse.inbound.AbstractEventParser$3.run(AbstractEventParser.java:279)
at java.lang.Thread.run(Thread.java:748)
2020-07-06 11:35:07,987 ERROR [destination = 1-236 , address = /192.168.3.100:3306 , EventParser] LogAlarmHandler:19 | destination:1-236[java.io.IOException: Received error packet: errno = 1236, sqlstate = HY000 errmsg = Could not find first log file name in binary log index file
at com.alibaba.otter.canal.parse.inbound.mysql.dbsync.DirectLogFetcher.fetch(DirectLogFetcher.java:102)
at com.alibaba.otter.canal.parse.inbound.mysql.MysqlConnection.dump(MysqlConnection.java:169)
at com.alibaba.otter.canal.parse.inbound.AbstractEventParser$3.run(AbstractEventParser.java:279)
at java.lang.Thread.run(Thread.java:748)
]
意思是在新主库上由于binlog名称翻转次数较少，binlog名称需要比原主库少，在新主库上找不到对应名称的binlog
3.使用删除的binlog文件名称，报如下错误：
2020-07-03 18:07:53,443 WARN [destination = 1-236 , address = /192.168.3.100:3306 , EventParser] MysqlEventParser:456 | prepare to find start position mysql-bin.000001:4:1593507861000
2020-07-03 18:07:53,443 WARN [destination = 1-236 , address = /192.168.3.100:3306 , EventParser] MysqlEventParser:205 | ---> find start position successfully, EntryPosition[included=false,journalName=mysql-bin.000001,position=4,serverId=<null>,gtid=<null>,timestamp=1593507861000] cost : 40ms , the next step is binlog dump
2020-07-03 18:07:53,444 INFO [destination = 1-236 , address = /192.168.3.100:3306 , EventParser] MysqlConnector:101 | disConnect MysqlConnection to /192.168.3.100:3306...
2020-07-03 18:07:53,446 INFO [destination = 1-236 , address = /192.168.3.100:3306 , EventParser] MysqlConnector:79 | connect MysqlConnection to /192.168.3.100:3306...
2020-07-03 18:07:53,447 INFO [destination = 1-236 , address = /192.168.3.100:3306 , EventParser] MysqlConnector:182 | handshake initialization packet received, prepare the client authentication packet to send
2020-07-03 18:07:53,447 INFO [destination = 1-236 , address = /192.168.3.100:3306 , EventParser] MysqlConnector:199 | client authentication packet is sent out.
2020-07-03 18:07:53,458 INFO [destination = 1-236 , address = /192.168.3.100:3306 , EventParser] MysqlConnection:293 | Register slave RegisterSlaveCommandPacket[reportHost=192.168.3.1,reportPort=49875,reportUser=canal_repl_user,reportPasswd=111111,serverId=10236,command=21]
2020-07-03 18:07:53,459 INFO [destination = 1-236 , address = /192.168.3.100:3306 , EventParser] MysqlConnection:321 | COM_BINLOG_DUMP with position:BinlogDumpCommandPacket[binlogPosition=4,slaveServerId=10236,binlogFileName=mysql-bin.000001,command=18]
2020-07-03 18:07:53,460 ERROR [destination = 1-236 , address = /192.168.3.100:3306 , EventParser] DirectLogFetcher:163 | I/O error while reading from client socket
java.io.IOException: Received error packet: errno = 1236, sqlstate = HY000 errmsg = Could not find first log file name in binary log index file
at com.alibaba.otter.canal.parse.inbound.mysql.dbsync.DirectLogFetcher.fetch(DirectLogFetcher.java:102)
at com.alibaba.otter.canal.parse.inbound.mysql.MysqlConnection.dump(MysqlConnection.java:169)
at com.alibaba.otter.canal.parse.inbound.AbstractEventParser$3.run(AbstractEventParser.java:279)
at java.lang.Thread.run(Thread.java:748)
2020-07-03 18:07:53,462 ERROR [destination = 1-236 , address = /192.168.3.100:3306 , EventParser] MysqlEventParser:301 | dump address /192.168.3.100:3306 has an error, retrying. caused by
java.io.IOException: Received error packet: errno = 1236, sqlstate = HY000 errmsg = Could not find first log file name in binary log index file
at com.alibaba.otter.canal.parse.inbound.mysql.dbsync.DirectLogFetcher.fetch(DirectLogFetcher.java:102)
at com.alibaba.otter.canal.parse.inbound.mysql.MysqlConnection.dump(MysqlConnection.java:169)
at com.alibaba.otter.canal.parse.inbound.AbstractEventParser$3.run(AbstractEventParser.java:279)
at java.lang.Thread.run(Thread.java:748)
2020-07-03 18:07:53,463 ERROR [destination = 1-236 , address = /192.168.3.100:3306 , EventParser] LogAlarmHandler:19 | destination:1-236[java.io.IOException: Received error packet: errno = 1236, sqlstate = HY000 errmsg = Could not find first log file name in binary log index file
at com.alibaba.otter.canal.parse.inbound.mysql.dbsync.DirectLogFetcher.fetch(DirectLogFetcher.java:102)
at com.alibaba.otter.canal.parse.inbound.mysql.MysqlConnection.dump(MysqlConnection.java:169)
at com.alibaba.otter.canal.parse.inbound.AbstractEventParser$3.run(AbstractEventParser.java:279)
at java.lang.Thread.run(Thread.java:748)
]
可以通过在主库上通过"flush logs"命令重新生成信息binlog，然后使用"show master status"查询信息位点，重新使用“CHANGE MASTER TO MASTER_LOG_FILE='log-bin.00000xx',MASTER_LOG_POS=xxx;”重新同步binlog。
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