Known Issues in Schema Registry

Learn about the known issues in Schema Registry, the impact or changes to the functionality, and the workaround.

CDPD-40380: Authorization checking issue when Kerberos is disabled

Due to an issue in Ranger, when Kerberos is disabled then it is not possible to check authorization.

  1. Open SR config in Cloudera Manager.
  2. Find the "" field.
  3. Replace GENERATED_RANGER_SERVICE_NAME with the actual name of the service.
  4. Restart Schema Registry.
CDPD-49304: AvroConverter does not support composite default values
AvroConverter cannot handle schemas containing a STRUCT type default value.
OPSAPS-66356: Schema Registry's integration with Atlas does not work in secure clusters where Ranger authorization is enabled
Due to an error in the default Ranger policies for Atlas, the integration between Schema Registry and Atlas does not work. As a result, Schema Registry related entities (metadata) are not created in Atlas. Viewing or monitoring schema entity relationships is not possible. If this issue is present in your cluster, the following exceptions will be present in the Schema Registry and Atlas server's log:
  • Schema Registry server log
    ERROR com.cloudera.dim.atlas.bootstrap.AtlasModelBootstrap: Error while setting up the Schema Registry model in Atlas.
  • Atlas Server log
    org.apache.atlas.exception.AtlasBaseException: schemaregistry is not authorized to perform create entity-def schema_metadata_info
  1. Access the Ranger Console (Ranger Admin web UI).
  2. Click the cm_atlas resource-based service.
  3. Add the schemaregistry user to the default policies.

    All policies that require an update will at minimum already contain the beacon, dpprofiler, atlas, admin, and nifi users. Adding the schemaregistry user to the Allow users to manage favorite searches default policy is not required.

  4. Restart the Schema Registry service.

    Restarting the services triggers the creation of the missing entities in Atlas.

CDPD-54379: KafkaJsonSerializer and KafkaJsonDeserializer do not allow null values
KafkaJsonSerializer and KafkaJsonDeserializer do not allow the data to be null, resulting in a NullPointerException (NPE).
CDPD-49217 and CDPD-50309: Schema Registry caches user group membership indefinitely

Schema Registry caches the Kerberos user and group information indefinitely and does not catch up on group membership changes.

Restart Schema Registry after group membership changes.
CDPD-56890: New schemas cannot be created following an upgrade
If you delete the latest version of a schema (the one with the highest ID) from the Schema Registry database before an upgrade, you might not be able to create new schemas after you upgrade the cluster to a newer version.
  1. Access the Schema Registry database. Go to Cloudera Manager > Schema Registry > Configuration and search for "database" if you don't know the name, host, or port of the Schema Registry database.
  2. Cross reference the ID's in the schemaVersionId column of the schmema_version_state table with the ID's found in the schema_version_info table.
  3. Delete all records from the schema_version_state table that contains a schemaVersionId not present in the schema_version_info table.
CDPD-58265: Schema Registry Client incorrectly applies SSL configuration
The Cloudera distributed Schema Registry Java client might fail to apply the SSL configurations correctly with concurrent access in Jersey clients due to a Jersey issue related to JDK.
Before using HttpsURLConnection in any form concurrently, call once in the custom client application.
OPSAPS-68139: Schema Registry does not apply cluster wide Kerberos principal mapping by default
Schema Registry does not apply the cluster-wide Kerberos auth-to-local (ATL) rules from the Core Setting service.
Manually set the Schema Registry Kerberos Name Rules property to match the configuration of the Core Setting service.
OPSAPS-68171: Schema Registry does not set Knox principal and service user as trusted proxies when using custom Kerberos principals
Schema Registry automatically sets the Knox principal name as a trusted proxy. If the Schema Registry Kerberos Name Rules property is set in deployments where custom Kerberos principals are used, Knox might not be allowed to work as a trusted proxy.
Manually configure the Knox user name by adding the following to Schema Registry Server Advanced Configuration Snippet (Safety Valve) for registry.yaml:
knox_principal_name=[***KNOX USER NAME***]
CDPD-48822: AvroConverter ignores default values when converting from Avro to Connect schema
AvroConverter does not propagate field default values when converting Avro schemas to Connect schemas.
CDPD-55381: Schema Registry issues authentication cookie for the authorized user, not for the authenticated one
When the authenticated user is different from the authorized user, which can happen when Schema Registry is used behind Knox, authorization issues can occur for subsequent requests as the authentication cookie in Schema Registry stores the authorized user.
Access Schema Registry directly, without using Knox, if possible. If not, ensure that the name of the end user that tries to connect does not begin with knox.
OPSAPS-68138: Schema Registry and Kafka cannot download policies from Ranger when using custom Kerberos principals
Ranger repositories created by the scripts that start Kafka, Kafka Connect and Schema Registry only add the principal name of related services to the repository users and the policies. In deployments where custom Kerberos principals are used, this can cause repository and policy download issues for Kafka, Kafka Connect and Schema Registry. Additionally, this can result in permission issues for related services.
Manually set the repository users and the policy users to refer to the correct service user names.
CDPD-60160: Schema Registry Atlas integration does not work with Oracle databases
Schema Registry is unable to create entities in Atlas if Schema Registry uses an Oracle database. The following will be present in the Schema Registry log if you are affected by this issue:
ERROR An error occurred while processing Atlas events.
java.lang.IllegalArgumentException: Cannot invoke com.hortonworks.registries.schemaregistry.AtlasEventStorable.setType on bean class 'class com.hortonworks.registries.schemaregistry.AtlasEventStorable' - argument type mismatch - had objects of type "java.lang.Long" but expected signature "java.lang.Integer"

This issue causes the loss of audit data on Oracle environments.

CDPD-48853: Schemas created with the Confluent Schema Registry API cannot be viewed in the UI
Schemas created in Cloudera Schema Registry using the Confluent Schema Registry API are not visible in the Cloudera Schema Registry UI.

In addition, the /api/v1/schemaregistry/search/schemas/aggregated endpoint of the Cloudera Schema Registry API does not return schemas created with the Confluent Schema Registry API.

A typical case where this issue can manifest is when you are using the Confluent Avro converter for SerDes in a Kafka Connect connector and the connector connects to Cloudera Schema Registry. That is, the key.converter and/or value.converter properties of the connector are set to io.confluent.connect.avro.AvroConverter, and key.converter.schema.registry.url and/or value.converter.schema.registry.url are set to a Cloudera Schema Registry server URL.