Linux Foundation Hyperledger Fabric Certified Practitioner HFCP Exam Questions

Answer : D

In Hyperledger Fabric, the correct subcommand to add a peer to a channel is peer channel join. This command is used by a peer node to join an existing channel. The command requires a block to be specified which typically is the genesis block of the channel, allowing the peer to synchronize with the channel's ledger from the beginning. Other commands like peer channel fetch, peer channel create, and peer channel update serve different purposes. peer channel fetch retrieves blocks from a channel, peer channel create is used to set up a new channel, and peer channel update modifies channel settings. Thus, peer channel join is the specific command used to connect a peer to a channel.

Answer : D

In Hyperledger Fabric, if a user submits a transaction with no matching function specified in the smart contract, the unknownTransaction function is invoked by default. This function serves as a catch-all method that can be used to handle cases where the transaction type is not recognized, providing a mechanism to manage or log these occurrences effectively .

Answer : C

In Hyperledger Fabric, when executing queries on the ledger, the difference between simple keys and composite keys is significant. Simple keys consist of a single attribute and are straightforward in their use for querying. In contrast, composite keys are formed by combining multiple attributes into a single key, allowing for more complex queries based on multiple fields. Composite keys enable richer, more flexible query capabilities that can facilitate refined searches and analyses within the ledger. This capability is particularly useful in scenarios where a single attribute is not sufficient to uniquely identify ledger entries or when queries need to filter based on multiple criteria.

Answer : B

The Fabric Gateway client APIs in Hyperledger Fabric streamline the transaction submission process by combining endorsement, submission, and commitment into a single function. This allows client applications to efficiently manage transaction submissions with a single line of code, specifically through the SubmitTransaction() function. This consolidation simplifies the interaction model for applications, enabling a focus on business logic rather than the underlying blockchain infrastructure details .

Answer : D

In the context of Hyperledger Fabric's chaincode, the endorsement policy plays a crucial role in defining the organizations that must sign a transaction proposal before it can be considered valid. This policy specifies which members of the network must agree (endorse) a transaction for it to be executed. The policy can require signatures from one or more specific organizations, depending on the chaincode's business logic and the network's governance requirements. This ensures that transactions are agreed upon by the relevant stakeholders, maintaining the integrity and trust within the network.

Answer : D

In Hyperledger Fabric, to enable CouchDB as the state database, the stateDatabase configuration option in the core.yaml file must be changed from goleveldb to CouchDB. This change directs the peer to use CouchDB instead of the default LevelDB for storing the world state, which can then be queried using rich queries and provides additional features like indexing.

Answer : B

Hyperledger Fabric allows different versions of the platform to coexist and interoperate on the same network through the use of channel capabilities. Channel capabilities enable organizations running different versions of Fabric binaries to participate on the same channel. These capabilities govern the features that are used by peer nodes and set the minimum version of the Fabric binaries that can be run by peers joined to the channel. This allows for heterogeneous network environments where different nodes might be running different versions of Fabric software .