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./kafka-features.sh upgrade [--release RELEASE] [--feature FEATURE --version VERSION] [--dry-run]
If The FEATURE and VERSION are given, send an UpdateFeaturesRequest to the controller for the given feature FEATURE to upgrade its version to VERSION. If RELEASE is given, send an UpdateFeaturesRequest for all of the features with the default versions from the given releasearguments can be repeated to indicate an upgrade of multiple features in one request. Alternatively, the RELEASE flag can be given to upgrade to the default versions of the specified release. If neither FEATURE nor RELEASE is given, this command will do nothing.
./kafka-features.sh downgrade --feature FEATURE --version VERSION [--unsafe, --dry-run]
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