Release notes

Corda Enterprise 4.0

This release of Corda Enterprise extends the Corda (open source) 4 release with new mission critical enterprise capabilities to include support for HSM (hardware security module) signing devices and improved high availability deployment configurations for Enterprise customers using DMZ environments.

Corda Enterprise 4.0 supports Linux for production deployments, with Windows and macOS support for development and demonstration purposes only. Please refer to product documentation for details.

Corda Enterprise 4.0 is operationally compatible with Corda (open source) 4.x and 3.x, and Corda Enterprise 3.x, while providing enterprise-grade features and performance.

Key new features and components

  • Multiple nodes behind a single firewallFacility to share an HA deployment of a Corda firewall (and shared Artemis message broker) by multiple nodes, reducing cost and complexity while providing increased security for end users. This also brings the added benefit of local only keys for Artemis access and as a result the corda TLS key and legal signing keys are fully separated.See Corda Firewall for further details.We have included a detailed Corda Firewall upgrade guide to simplify the migration from Corda Enterprise 3.x to use these new features.
  • Hardware Security Module (HSM) supportSupport for node CA and legal identity signing keys in hardware security module providing clients with increased security. HSMs are standard in many enterprise organizations, store and safeguard cryptographic keys in tamper-proof hardware. Vendors supported include Azure Key Vault, Gemalto Luna and Utimaco.See HSM support for more information.
  • High Availability improvementsThis release builds on the Hot-Cold High Availability configuration available in Corda Enterprise 3.x as follows:
    • Standalone Artemis MQ broker (previously was always embedded within the node process) for peer to peer messaging. This ultimately reduces VM footprint of node processes and facilitates configurability of a single HA messaging broker component.
    • New configuration mode that enables using Artemis broadcasts as an alternative to Zookeeper to manage HA nodes and associated Firewall components (float and bridge).

See Hot-cold high availability deployment for further details.

  • Operational Deployment improvementsEnterprise 4 introduces architectural improvements that optimize larger scale deployments, reduce the cost of infrastructure, and minimize the operational complexity of multi-node hosting:
    • Management of multiple clusters of HA nodes with a single interface. Enterprise 4 achieves this with Zookeeper.
    • Shareable Artemis messaging servers across nodes allows for less infrastructure components in a multi-node configuration.

Additionally, we have added support for the RedHat distribution of Artemis called Red Hat AMQ.

  • Performance Test Suite for benchmarkingThe Performance Test suite enables customers to run their own benchmarks for comparative testing across different configurations and identifying hardware and resource sizing requirements. Using this test framework, customers can test and validate their infrastructure performance and determine whether or not improvements are needed before going live.See Performance Test Suite and Corda Enterprise Performance Testing for further details.

  • Node health survey toolThis is a simple tool that collects and packages up material that R3 Support will need to be able to help a customer with a support request, including things like:>

    • a censored version of the config (i.e., without passwords, etc.),
    • logs from the last 3 days (if the user is happy to include these),
    • version numbers of Corda, the Java virtual machine and the operating system,
    • networking information with DNS lookups to various endpoints (database, network map, doorman, external hosts),
    • a copy of the network parameters file,
    • a list of installed CorDapps (including their file sizes and checksums),
    • a list of the files in the drivers directory,
    • a copy of the node information file for the node and a list of the ones in the additional-node-infos directory.

In future versions of Corda, we will expand on this tool’s capabilities for it to be a complete deployment verification tool, also usable with more complex, high availability deployments.

  • RPC client compatibilityWith Corda (open source) 4 upgrading to use the AMQP serialisation protocol for RPC communication, it is now possible to communicate remotely to a Corda 4 or Corda Enterprise 4 node using either of the respective 4.x distributions’ RPC client binary library.
  • Operational Compatibility With Open Source CordaCorda Enterprise 4.0 maintains the wire stability and compatibility assurance with open-source releases of Corda from version 3.0 onwards.It delivers forward compatibility with future versions of Corda Enterprise:
    • Is operationally compatible with future versions of Corda Enterprise.
    • Is upgradeable to future version of Corda Enterprise, preserving transaction and other data.

It delivers operational compatibility with open-source Corda: * Can be used in networks seamlessly transacting with nodes running Corda 3.x and future versions. * Can run CorDapps developed on Corda 3.x and future versions. Note that some database changes may be required to achieve this. See Upgrading your node to Corda 4 for more information. * Is compatible with ledger data created using Corda 3.x and future versions.

Further improvements, additions and changes

  • Corda Firewall (bridge and float) components now have dedicated private keystores and passwords. A special tool has been created to simplify generation of the keystores. See Firewall keystore generation for further details.
  • A number of HA utilities to improve the setup and configuration of enterprise deployments. See HA Utilities for further details.
  • Passwords may now be obfuscated in configuration files. See Configuration Obfuscator for further details.
  • Oracle Wallet support: you can now connect to an Oracle database using credentials stored in an Oracle Wallet. See Connecting to Oracle using Oracle Wallet for further details.
  • Improve diagnostics for operational support and troubleshooting. Stacktraces are still printed to the log files, but errors printed to the console include an automatically derived error code instead. These error codes make it easier to discover diagnostics and troubleshooting steps for various error conditions, and can also be used to find corresponding information in log files or to correlate errors across multiple nodes in a broader deployment. The introduction of error codes also allows us to maintain and continuously improve our error information and recovery guidelines on a different cadence to that of our releases.
  • Improved Notary retry support Client-side notarisation flows have special retry logic that enables failover in case a member of the notary cluster goes down while processing a request. This release includes a fix that disables retries when talking to a single-node notary, as it does not provide any benefit. Additionally, the maximum retry limit has been dropped, and notarisations will be retried indefinitely. This is to prevent potential transaction loss in case of network issues or misconfiguration where the notary is unable to send back a response to the client.
  • Notary support The experimental Raft notary implementation has been deprecated in favour of the MySQL-based HA notary implementation (see Setting up a HA notary service). The experimental BFT-Smart notary implementation has been deprecated – a fully supported BFT implementation is under development.
  • Flow hospital enhancements New in Corda Enterprise 4.0, if a node receives a message from a peer to initiate a flow that is not recognised by the node, perhaps due to the CorDapp not being installed, rather than sending an error back to the initiating peer node it is kept in the hospital until the CorDapp is installed and the node restarted. Furthermore, in addition to the existing hospitalisation for flow errors in the FinalityHandler of Corda Enterprise 3, flow errors in the new inlined ReceiveFinalityFlow replacement will also be hospitalised similarly.
  • Improved Database Management and Migration Tooling Corda Enterprise 4.0 improves the database administration tool for tracking, managing and applying database schema and data changes (for both Corda infrastructure and CorDapps). See database migration for further details.
  • Support for class evolution using non-nullable properties if you supply an evolution constructor which fills in the missing property values.

Known issues

The following list contains important known issues identified in this release. We will endeavour to fix these in future releases of Corda.

  • Prior to Corda Enterprise 4.0 all CorDapps were classloaded in the same applications classloader, with no isolation or visibility constraints. With the introduction of the Attachments Classloader in for transaction verification, a CorDapp JAR is now only classloaded if there is at least one class that implements the Contract interface. Where a Contract CorDapp previously depended on classes packaged in a separate JAR (eg. a 3rd party library, common classes or other CorDapp contracts), these must now be included in the same Contract CorDapp JAR. Please read Contract CorDapps JARs with external dependencies for a more detailed explanation and a reference example.

  • The experimental finance CorDapp compiled against Corda 3.3 or Enterprise Corda 3.2 and run on Corda Enterprise 4.0 is not guaranteed to interoperate with its upgraded equivalent Corda 4 version compiled against Corda 4.0 or Corda Enterprise 4.0 and running on Corda Enterprise 4.0.See CorDapp Upgradeability Guarantees for further information.

  • Certificate revocation revokes identities, not keys, and is currently irreversible. If your keys are lost or compromised, new keys cannot be re-issued with the same X.500/legal entity name. It is strongly advised to backup your certificates appropriately and to apply sensible policy for management of private keys.

Upgrade notes

As per previous major releases, we have provided a comprehensive upgrade notes ( Upgrading CorDapps to Corda Enterprise 4.0) to ease the upgrade of CorDapps to Corda Enterprise 4.0. In line with our commitment to API stability, code level changes are fairly minimal.

For developers, switching CorDapps built using Corda (open source) 4.x to Corda Enterprise 4.0 is mostly effortless, and simply requires making the Corda Enterprise binaries available to Gradle, and changing two variables in the build file:

ext.corda_release_version = '4.0'
ext.corda_release_distribution = 'com.r3.corda'

For node operators, it is advisable to follow the instructions outlined in Upgrading a Corda Node.

Visit the for more information about Corda Enterprise. Customers that have purchased support can access it online at