In a Kafka consumer group, if one consumer constantly connects and disconnects, does it affect reading by other consumers in the same group?

If a single consumer in a Kafka consumer group constantly connects and disconnects, it can affect the entire group's operation. When a consumer disconnects or connects, a rebalance of partitions among the group's consumers occurs. During rebalance, data reading is paused for a short time, which can lead to delays in message processing by other consumers.

Thus, unstable behavior of one consumer impacts the entire group, reducing overall performance and increasing response time. To minimize this impact, it is advisable to investigate the causes of frequent reconnections and address them, such as optimizing timeouts, checking network connections, or fixing errors in the consumer code.