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• When moving between patch (also known as incremental) version changes such as 0.1.0 to 0.1.1 users should be safe to assume a clean upgrade can occur with no risk of behavior changes other than bug fixes and no compatibility issues.
• When moving between minor changes such as 0.1.0 to 0.2.0 users can expect new behaviors and bug fixes but backward compatibility should be protected.
• When moving between major changes such as 0.x.y to 1.0.0 t here may be backward compatibility impacting changes largely focused on removal of deprecated items.
  

Migrating to 1.17.0

• This release deprecated support for RocksDBFlowFileRepository. The RocksDB repository is packaged in a separate NAR named nifi-rocksdb-nar, available for download from Maven Central
• This release removed Hive 1.2 components from the standard release binary. The nifi-hive-nar and nifi-hive-services-api-nar modules can be downloaded from Maven Central

Migrating from 1.15.0 to 1.16.0

• This release adds HTTP request logging and updates the default logback.xml configuration. Deployments with customized Logback configurations should add a new request appender and request logger configuration to avoid writing HTTP requests to nifi-app.log
• This release removed support for Elasticsearch 2 components. Version 1.15.3 of nifi-elasticsearch-nar can be downloaded from Maven Central
• This release removed support for Elasticsearch 5 components. Version 1.15.3 of nifi-elasticsearch-5-nar can be downloaded from Maven Central
• This release removed support for Kite components. Version 1.15.3 of nifi-kite-nar can be downloaded from Maven Central
• This release removed support for Lumberjack components. Version 1.15.3 of nifi-lumberjack-nar can be downloaded from Maven Central
• This release removed support for Kafka components supporting Kafka versions prior to 1.0. Version 1.15.3 of nifi-kafa-0-nar modules can be downloaded from Maven Central
• This release removed support for InfluxDB from the standard NiFi binary download. The nifi-influxdb-nar can be downloaded from Maven Central
• This release removed the nifi-processor-utils JAR and refactored classes into several new modules under nifi-extension-utils. When rebuilding custom components to depend on 1.16.0 libraries, it will be necessary to remove dependencies on nifi-processor-utils. Custom NAR bundles, already compiled using versions prior to 1.16.0, can continue to be used in runtime deployments
• This release removed support for MySQL 5.6 /5.7 and Postgres 9.x for NiFi Registry's database, supported databases are now H2, Postgres 10.x - 14.x and MySQL 8.x.
• NOTE: A bug was discovered after the release (NIFI-9836) that causes NiFi Registry to only work with H2. The issue is addressed in main and will be resolved in 1.16.1.

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