当发现修改了数据库后修改的数据并没有发送到MQ，通过查看Canal的日志发现下边的错误。
进入Canal目录，查看日志：
cd /data/soft/canal/logs
tail -f logs/xzb-canal.log
Canal报错如下：
2023-09-22 08:34:40.802 [destination = xzb-canal , address = /192.168.101.68:3306 , EventParser] WARN c.a.o.c.p.inbound.mysql.rds.RdsBinlogEventParserProxy - ---> find start position successfully, EntryPosition[included=false,journalName=mysql-bin.000055,position=486221,serverId=1,gtid=,timestamp=1695341830000] cost : 13ms , the next step is binlog dump
2023-09-22 08:34:40.811 [destination = xzb-canal , address = /192.168.101.68:3306 , EventParser] ERROR c.a.o.canal.parse.inbound.mysql.dbsync.DirectLogFetcher - 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) ~[canal.parse-1.1.5.jar:na]
at com.alibaba.otter.canal.parse.inbound.mysql.MysqlConnection.dump(MysqlConnection.java:238) [canal.parse-1.1.5.jar:na]
at com.alibaba.otter.canal.parse.inbound.AbstractEventParser$1.run(AbstractEventParser.java:262) [canal.parse-1.1.5.jar:na]
at java.lang.Thread.run(Thread.java:748) [na:1.8.0_181]
找到关键的位置：Could not find first log file name in binary log index file
根据日志分析是Canal找不到mysql-bin.000055 的486221位置，原因是mysql-bin.000055文件不存在，这是由于为了节省磁盘空间将binlog日志清理了。
解决方法：
把canal复位从最开始开始同步的位置。
- 首先重置mysql的bin log：
连接mysql执行：reset master
执行后所有的binlog删除，从000001号开始
通过show master status;查看 ，结果显示 mysql-bin.000001
- 先停止canal
docker stop canal
- 删除meta.dat
rm -rf /data/soft/canal/conf/meta.dat
- 再启动canal
docker start canal
