We have debezium connected to a multi-master mysql cluster with snapshot mode on 'Initial'. Sometimes we get these errors:
org.apache.kafka.connect.errors.ConnectException: The connector is trying to read binlog starting at GTIDs 6372424d-a375-ee14-49d4-68734c2fd7fb:1-377469,9aa5d14c-5c8b-11eb-a22a-005
056a27f08:1 and binlog file 'mysql-bin.000095', pos=58856251, skipping 0 events plus 0 rows, but this is no longer available on the server.
Reconfigure the connector to use a snapshot when needed.
First of all we would like to have a better understanding of what is happening here. Is it 'normal' that this exception occurs in a percona/mysql multi-master setup sometimes? For example when 1 of the mysql nodes gets cut off the other nodes and debezium was connected to that node?
When looking for a solution, I understand from the documentation that we need some kind of snapshot mode and 'when_needed' seems to be the most suitable in our case. Some aspects of it are still unclear to us though.
- is data loss possible with this snapshot mode?
- or the other way around: is it possible that some events get sent out twice by debezium?
Thanks in advance for your reply!