Can I see the Kafka settings the server actually applied?

Query, MergeTree and server settings can all be inspected from SQL, with the effective value next to the default. Kafka is the odd one out: behavior comes from engine settings in CREATE TABLE plus librdkafka properties in a <kafka> section of the server config, a pass-through bag of keys. A misspelled key or the wrong file leaves the consumer on defaults and nothing shows which keys were accepted. I asked for system.kafka_settings with name, effective value, default, a changed flag and consumer/producer scope.

Nothing yet. The issue is open, labelled feature, comp-message-queues and external, with no comments.

The neighbour that exists is system.kafka_consumers, which shows per-consumer state: assignments, offsets, last poll and commit times, rebalance counters, exceptions and the raw librdkafka statistics in rdkafka_stat. That tells you what a consumer is doing, not what configuration it started with. On 26.4:

SELECT * FROM system.kafka_settings;

Code: 60. DB::Exception: Unknown table expression identifier 'system.kafka_settings' ... (UNKNOWN_TABLE)

This needs a server to go further, so I have not exercised it against a broker. There is no clean workaround; you infer effect from behavior and logs. See Kafka consumers status and operating Kafka engine tables. I still want the table, since a typo is easiest to make and hardest to see in exactly this layer.