# KRaft and AclAuthorizer

**URL:** <https://forum.confluent.io/t/kraft-and-aclauthorizer/4280>\
**Category:** Ops\
**Created:** [24 February 2022 10:44 UTC](https://forum.confluent.io/t/kraft-and-aclauthorizer/4280 "2022-02-24T10:44:20Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![webfrank](https://sea1.discourse-cdn.com/flex019/user_avatar/forum.confluent.io/webfrank/32/1628_2.png) [@webfrank](https://forum.confluent.io/u/webfrank)\
**Post date:** [24 February 2022 10:44 UTC](https://forum.confluent.io/t/kraft-and-aclauthorizer/4280/1 "2022-02-24T10:44:20Z")

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Hi, I would like to enable AclAuthorizer on a KRaft cluster but I receive this error:

```auto
ERROR [ControllerServer id=2] Fatal error during controller startup. Prepare to shutdown (kafka.server.ControllerServer)
java.lang.NullPointerException
at kafka.zk.KafkaZkClient$.apply(KafkaZkClient.scala:1965)
at kafka.security.authorizer.AclAuthorizer.configure(AclAuthorizer.scala:182)
at kafka.server.ControllerServer.$anonfun$startup$11(ControllerServer.scala:118)
at kafka.server.ControllerServer.$anonfun$startup$11$adapted(ControllerServer.scala:118)
at scala.Option.foreach(Option.scala:437)
at kafka.server.ControllerServer.startup(ControllerServer.scala:118)
at kafka.server.KafkaRaftServer.$anonfun$startup$1(KafkaRaftServer.scala:109)
at kafka.server.KafkaRaftServer.$anonfun$startup$1$adapted(KafkaRaftServer.scala:109)
at scala.Option.foreach(Option.scala:437)
at kafka.server.KafkaRaftServer.startup(KafkaRaftServer.scala:109)
at kafka.Kafka$.main(Kafka.scala:109)
at kafka.Kafka.main(Kafka.scala)6b3

```

It seems I need to specify a zookeeper url but I do not have it as I’m using KRaft.

How should I configure the AclAuthorizer in this situation?

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<div class="post-metadata">

**Author:** ![rmoff](https://sea1.discourse-cdn.com/flex019/user_avatar/forum.confluent.io/rmoff/32/3_2.png) [@rmoff](https://forum.confluent.io/u/rmoff)\
**Post date:** [24 February 2022 11:29 UTC](https://forum.confluent.io/t/kraft-and-aclauthorizer/4280/2 "2022-02-24T11:29:25Z")

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Hi @webfrank, welcome to the forum 🙂  
Can you detail what version of Kafka you’re using, and what steps you’re taking to enable AclAuthorization?

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<div class="post-metadata">

**Author:** ![rick](https://sea1.discourse-cdn.com/flex019/user_avatar/forum.confluent.io/rick/32/49_2.png) [@rick](https://forum.confluent.io/u/rick)\
**Post date:** [24 February 2022 16:59 UTC](https://forum.confluent.io/t/kraft-and-aclauthorizer/4280/3 "2022-02-24T16:59:07Z")

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@webfrank To use the AclAuthorizer with Kraft mode, you’ll still need a ZK cluster and you’ll configure it as normal. Please note this Jira related to a new Kraft Authorizer which has been merged into the 3.2 branch [[KAFKA-13646] Implement KIP-801: KRaft authorizer - ASF JIRA](https://issues.apache.org/jira/browse/KAFKA-13646)