Migrating from DataStax Enterprise to Apache Cassandra
This guide describes how to migrate from DataStax Enterprise (DSE) to open-source Apache Cassandra. It covers the proprietary components that run only on DSE, the open-source replacements for each of them, and the end-to-end migration process with go/no-go checkpoints and rollback procedures at every stage.
DSE is a proprietary distribution built around Apache Cassandra. Over successive releases it added components, such as a search engine derived from Apache Solr, an analytics layer built on Apache Spark, a graph database, an advanced security module, the NodeSync continuous-repair mechanism, and the OpsCenter management tool, that tie a deployment to the DSE distribution. Migrating to open-source Apache Cassandra removes that dependency, restores access to the latest community releases and security patches, and broadens the choice of tooling and commercial support.
Why migrate from DSE to Apache Cassandra?
Section titled “Why migrate from DSE to Apache Cassandra?”- Access to current releases. DSE is based on a fork of Apache Cassandra 3.11, which reached end of life (EOL) in 2024. Open-source Cassandra has since shipped 4.0, 4.1, and 5.0, each with substantial storage-engine, streaming, and security improvements that are not available in DSE.
- No single-vendor dependency. With open-source Cassandra, the latest release is always accessible, with security patches from the community and a choice of tooling and support vendors.
- Modern capabilities. Cassandra 5.0 introduces Storage-Attached Indexes (SAI), the Unified Compaction Strategy, trie-based memtables and SSTables, and vector search, none of which exist in the DSE 3.11 lineage.
For the cost, risk, and support case, including how open-source security compares to DSE Advanced Security, see the business case and DSE proprietary features.
Migration masterclass webinar
Section titled “Migration masterclass webinar”This recorded AxonOps masterclass webinar covers the DataStax Enterprise to Apache Cassandra migration. AxonOps runs masterclass webinars regularly; browse the full series of AxonOps Masterclasses.
Watch on YouTube
If the player above does not load, watch directly on YouTube: AxonOps Masterclass: DataStax Enterprise to Apache Cassandra Migration.
The two migration paths
Section titled “The two migration paths”There are two supported paths from DSE to Apache Cassandra. The right one depends primarily on the DSE version, which determines SSTable and protocol compatibility (see Assessment).
| Path | When to use | Summary |
|---|---|---|
| CDM + ZDM Proxy (recommended, all versions) | Any DSE version; the safest path for DSE 6.0+ | Stand up a new open-source Apache Cassandra cluster, route application traffic through the Zero-Downtime Migration (ZDM) Proxy (dual-writes), bulk-copy existing data with Cassandra Data Migrator (CDM), validate, then cut over. |
| Second datacenter (alternative, DSE 5.1 and earlier) | DSE 5.1 and earlier, where adding an open-source datacenter to the existing ring is acceptable | Add an open-source Apache Cassandra datacenter (matching the DSE release's underlying Cassandra version) to the existing ring, rebuild and repair onto it under controlled load, validate, cut over, decommission the DSE datacenter, then upgrade to 5.0. |
CDM + ZDM Proxy path (recommended, all versions)
Section titled “CDM + ZDM Proxy path (recommended, all versions)”In this path, the application connects only to the AxonOps fork of the ZDM Proxy, which dual-writes to the origin DSE cluster and a separate target Apache Cassandra cluster while Cassandra Data Migrator (CDM) copies the existing data across. Once the target is validated, reads are switched to the target through the proxy. The application then cuts over to connect directly to it, and the DSE cluster is decommissioned (see ZDM Proxy and CDM Setup for the detailed topology).
Second-datacenter path (alternative, DSE 5.1 and earlier)
Section titled “Second-datacenter path (alternative, DSE 5.1 and earlier)”A single logical cluster holds both datacenters in this path: the existing DSE
datacenter and a new one running the DSE release's underlying Cassandra
version. Replication and nodetool rebuild
stream data to the new datacenter under controlled load, and a full repair then
establishes consistency. Once the new datacenter is validated, the application
moves across, the DSE datacenter is decommissioned, and the cluster is upgraded
to Cassandra 5.0 in sequential major-version steps (see
Second Datacenter Migration for the detailed
procedure).
DSE 6.0+: the second-datacenter path is expert-only
On DSE 6.0+ the second-datacenter path is only for teams who know exactly what they are doing, and it must be proven with a proof of concept first. For DSE 6.0+, the safest and recommended approach is the CDM + ZDM Proxy data migration to a separate target cluster. If in doubt, talk to AxonOps.
Both paths share the same preparatory work (assessment, monitoring, and component migration) and diverge only at the data-migration stage.
The phased process
Section titled “The phased process”The migration is structured as a controlled project with defined checkpoints. Each phase has explicit go/no-go criteria and a rollback procedure.
| Phase | Focus | Page |
|---|---|---|
| 0 | Assess the estate, audit the schema, choose the path | Assessment |
| 1 | Install monitoring on the DSE cluster, capture baselines | Monitoring & Baseline |
| 2 | Replace proprietary components with open-source equivalents | Component Migration |
| 3 | Migrate the data: set up ZDM/CDM and run the migration, or use the second-datacenter path | Data Migration |
| 4 | Validate health, consistency, and performance | Validation |
| 5 | Cut over to the target and decommission DSE | Cutover |
| 6 | Settle into day-2 operations | Post-Migration Operations |
| Ref | ZDM/CDM caveats and troubleshooting | Operational Caveats |
Review the DSE proprietary features reference to understand which proprietary components are in play and what each one is replaced with.
How AxonOps helps
OpsCenter, DSE's management tool, does not support open-source Cassandra. It stops working the moment DSE nodes are replaced. This leaves a day-2 operations gap (monitoring, repair, backup, alerting) that must be filled before cutover. AxonOps is a purpose-built operations platform that monitors both DSE and open-source Cassandra simultaneously, so the same tool covers the entire migration and the cluster afterwards. For support, tooling, or help replacing OpsCenter, see the AxonOps Cassandra offering.
Frequently asked questions
Section titled “Frequently asked questions”Is DataStax Enterprise (DSE) end of life?
Section titled “Is DataStax Enterprise (DSE) end of life?”DSE 6.x is built on a fork of Apache Cassandra 3.11, a release line the Apache Cassandra project declared end of life in 2024. The open-source foundation from which DSE derives is no longer maintained by the upstream community, so fixes and ongoing maintenance fall to the DSE vendor rather than the broader open-source community, and keeping a distribution built on an end-of-life database release secure and current grows more costly over time as the gap from active development widens. DSE is further constrained to Java 8 (released 2014) and Java 11 (released 2018), both past their Oracle Premier Support windows (Java 8 ended in March 2022, Java 11 in September 2023). Apache Cassandra 5.0 is actively maintained by the upstream community and runs on current JDKs (Java 11 and Java 17), with Apache Cassandra 6.0 set to add Java 21 and later, so a migration moves the estate onto a supported database release and supported Java runtimes that keep pace with the JDK release cadence.
Can DSE be migrated to Apache Cassandra without downtime?
Section titled “Can DSE be migrated to Apache Cassandra without downtime?”Yes. The CDM + ZDM Proxy path dual-writes to both clusters and copies existing data in the background, so the application keeps serving traffic throughout.
Which DSE versions can use the second-datacenter path?
Section titled “Which DSE versions can use the second-datacenter path?”DSE 5.1 and earlier, which remain wire- and SSTable-compatible with their underlying Apache Cassandra version. DSE 6.0+ should use the CDM + ZDM Proxy path.
Is Apache Cassandra as secure as DSE Advanced Security?
Section titled “Is Apache Cassandra as secure as DSE Advanced Security?”Yes. Open-source Cassandra 4.x and 5.0 add audit logging, dynamic data masking, CIDR and datacenter role restrictions, and certificate-based internode TLS, capabilities that post-date the DSE 3.11 lineage. See DSE proprietary features.