问题一:
ERROR c.a.otter.canal.parse.inbound.mysql.MysqlEventParser - dump address /192.168.1.50:3306 has an error, retrying. caused by
com.alibaba.otter.canal.parse.exception.CanalParseException: can't find start position for example
原因:meta.dat 中保存的位点信息和数据库的位点信息不一致;导致canal抓取不到数据库的动作;
解决方案:删除meta.dat删除,再重启canal,问题解决;
集群操作:进入canal对应的zookeeper集群下,删除节点/otter/canal/destinations/xxxxx/1001/cursor ;重启canal即可恢复;
问题二:
java.lang.OutOfMemoryError: Java heap space
canal消费端挂了太久,在zk对应conf下节点的
/otter/canal/destinations/test_db/1001/cursor 位点信息是很早以前,导致重启canal时,从很早以前的位点开始消费,导致canal服务器内存爆掉
监听数据库变更,只有TransactionBegin/TransactionEnd,没有拿到数据的EventType;
原因可能是canal.instance.filter.black.regex=.*\\..*导致,改canal.instance.filter.black.regex=再重启试试;
问题三:
ERROR com.alibaba.otter.canal.common.alarm.LogAlarmHandler - destination:fdyb_db[com.alibaba.otter.canal.parse.exception.CanalParseException: com.alibaba.otter.canal.parse.exception.CanalParseException: parse row data failed.
Caused by: com.alibaba.otter.canal.parse.exception.CanalParseException: parse row data failed.
Caused by: com.alibaba.otter.canal.parse.exception.CanalParseException: com.google.common.collect.ComputationException: com.alibaba.otter.canal.parse.exception.CanalParseException: fetch failed by table meta:
mysql
.
pds_4490277
Caused by: com.google.common.collect.ComputationException: com.alibaba.otter.canal.parse.exception.CanalParseException: fetch failed by table meta:
mysql
.
pds_4490277
Caused by: com.alibaba.otter.canal.parse.exception.CanalParseException: fetch failed by table meta:
mysql
.
pds_4490277
Caused by: java.io.IOException: ErrorPacket [errorNumber=1142, fieldCount=-1, message=SELECT command denied to user 'cy_canal'@'11.217.0.224' for table 'pds_4490277', sqlState=42000, sqlStateMarker=#]
with command: desc
mysql
.
pds_4490277
分析:mysql系统表权限较高,canal读该表的binlog失败,位点无法移动
解决:将配置项中黑名单加上mysql下的所有表:canal.instance.filter.black.regex = mysql\\..* ,修改后canal集群不需要重启即可恢复;
其它注意点:检查下CanalConnector是否调用subscribe(filter)方法;有的话,filter需要和instance.properties的canal.instance.filter.regex一致,否则subscribe的filter会覆盖instance的配置,如果subscribe的filter是.\\..,那么相当于你消费了所有的更新数据。
问题四:
现象:数据库修改后,canal应用感知不到binlog,数据无法正常消费处理;