2022 New Training Course CCDAK Tutorial Preparation Guide [Q34-Q48]

2022 新トレーニングコース CCDAKチュートリアル準備ガイド [Q34-Q48］

11月 2, 2022 管理者 0 コメント

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2022 New Training Course CCDAK Tutorial Preparation Guide

Dumps of CCDAK Cover all the requirements of the Real Exam

質問34
By default, which replica will be elected as a partition leader? (select two)

Preferred leader broker if it is in-sync and auto.leader.rebalance.enable=true

Any of the replicas

Preferred leader broker if it is in-sync and auto.leader.rebalance.enable=false

An in-sync replica

Preferred leader is a broker that was leader when topic was created. It is preferred because when partitions are first created, the leaders are balanced between brokers. Otherwise, any of the in-sync replicas (ISR) will be elected leader, as long as unclean.leader.election=false (by default)

質問35
StreamsBuilder builder = new StreamsBuilder();
KStream<String, String> textLines = builder.stream(“word-count-input”); KTable<String, Long> wordCounts = textLines
.mapValues(textLine -> textLine.toLowerCase())
.flatMapValues(textLine -> Arrays.asList(textLine.split(“W+”)))
.selectKey((key, word) -> word)
.groupByKey()
.count(Materialized.as(“Counts”));
wordCounts.toStream().to(“word-count-output”, Produced.with(Serdes.String(), Serdes.Long())); builder.build(); What is an adequate topic configuration for the topic word-count-output?

max.message.bytes=10000000

cleanup.policy=delete

compression.type=lz4

cleanup.policy=compact

Result is aggregated into a table with key as the unique word and value its frequency. We have to enable log compaction for this topic to align the topic’s cleanup policy with KTable semantics.

質問36
Suppose you have 6 brokers and you decide to create a topic with 10 partitions and a replication factor of 3. The brokers 0 and 1 are on rack A, the brokers 2 and 3 are on rack B, and the brokers 4 and 5 are on rack C.
If the leader for partition 0 is on broker 4, and the first replica is on broker 2, which broker can host the last replica? (select two)

When you create a new topic, partitions replicas are spreads across racks to maintain availability. Hence, the Rack A, which currently does not hold the topic partition, will be selected for the last replica

質問37
The exactly once guarantee in the Kafka Streams is for which flow of data?

Kafka => Kafka

Kafka => External

External => Kafka

Kafka Streams can only guarantee exactly once processing if you have a Kafka to Kafka topology.

質問38
You are using JDBC source connector to copy data from 2 tables to two Kafka topics. There is one connector created with max.tasks equal to 2 deployed on a cluster of 3 workers. How many tasks are launched?

we have two tables, so the max number of tasks is 2

質問39
If you enable an SSL endpoint in Kafka, what feature of Kafka will be lost?

Cross-cluster mirroring

Support for Avro format

Zero copy

Exactly-once delivery

With SSL, messages will need to be encrypted and decrypted, by being first loaded into the JVM, so you lose the zero copy optimization. See more information herehttps://twitter.com/ijuma/status/1161303431501324293?s=09

質問40
A producer application in a developer machine was able to send messages to a Kafka topic. After copying the producer application into another developer’s machine, the producer is able to connect to Kafka but unable to produce to the same Kafka topic because of an authorization issue. What is the likely issue?

Broker configuration needs to be changed to allow a different producer

You cannot copy a producer application from one machine to another

The Kafka ACL does not allow another machine IP

The Kafka Broker needs to be rebooted

ACLs take “Host” as a parameter, which represents an IP. It can be * (all IP), or a specific IP. Here, it’s a specific IP as moving a producer to a different machine breaks the consumer, so the ACL needs to be updated

質問41
Select all that applies (select THREE)

min.insync.replicas is a producer setting

acks is a topic setting

acks is a producer setting

min.insync.replicas is a topic setting

min.insync.replicas matters regardless of the values of acks

min.insync.replicas only matters if acks=all

acks is a producer setting min.insync.replicas is a topic or broker setting and is only effective when acks=all

質問42
Where are the dynamic configurations for a topic stored?

In Zookeeper

In an internal Kafka topic __topic_configuratins

In server.properties

On the Kafka broker file system

Dynamic topic configurations are maintained in Zookeeper.

質問43
A topic has three replicas and you set min.insync.replicas to 2. If two out of three replicas are not available, what happens when a consume request is sent to broker?

Data will be returned from the remaining in-sync replica

An empty message will be returned

NotEnoughReplicasException will be returned

A new leader for the partition will be elected

With this configuration, a single in-sync replica is still readable, but not writeable if the producer using acks=all

質問44
Which of the following Kafka Streams operators are stateless? (select all that apply)

map

filter

flatmap

branch

groupBy

aggregate

Seehttps://kafka.apache.org/20/documentation/streams/developer-guide/dsl-api.html#stateless-transformations

質問45
In Avro, removing a field that does not have a default is a __ schema evolution

breaking

full

backward

前方

Clients with new schema will be able to read records saved with old schema.

質問46
A Zookeeper ensemble contains 5 servers. What is the maximum number of servers that can go missing and the ensemble still run?

majority consists of 3 zk nodes for 5 nodes zk cluster, so 2 can fail

質問47
A consumer has auto.offset.reset=latest, and the topic partition currently has data for offsets going from 45 to 2311. The consumer group never committed offsets for the topic before. Where will the consumer read from?

offset 2311

offset 0

offset 45

it will crash

Latest means that data retrievals will start from where the offsets currently end

質問48
Which of the following statements are true regarding the number of partitions of a topic?

The number of partitions in a topic cannot be altered

We can add partitions in a topic by adding a broker to the cluster

We can add partitions in a topic using the kafka-topics.sh command

We can remove partitions in a topic by removing a broker

We can remove partitions in a topic using the kafka-topics.sh command

We can only add partitions to an existing topic, and it must be done using the kafka-topics.sh command