Kafka data is not lost

1, kafka broker downtime, data not syncing some follower, the follower was elected after the leader, in order to avoid loss of data, set the following parameters:

topic: replication.factor more than 1 
server: min.insync.replicas greater than 1, at least one follower to keep in touch 
Producer: ACKs = = MAX All retries to write all replication writes considered success, failure, unlimited retries.