Cassandra Admin study guide
Cassandra Admin · Work through your exam, one topic at a time.
The Cassandra Admin credential certifies that a candidate can run Apache Cassandra in production rather than merely write CQL against it. It targets database administrators, SREs and platform engineers who already touch a cluster and want their operational judgment validated: reading nodetool output under pressure, sizing a compaction strategy, deciding when a repair window is safe, and knowing which consistency level actually protects a given write. The Cassandra Admin study guide has 8 sections and about 2,566 words.
01Cassandra Architecture and the Distributed Ring
This domain tests how Cassandra works as a masterless, peer-to-peer ring: how nodes discover each other, how data is placed on token ranges, and how coordinators, replicas, and storage engines cooperate. Expect questions on gossip, seed nodes, snitches, partitioners, virtual nodes, and the write/read path.
316 words, about 2 min02Installation, Configuration, and Cluster Provisioning
This domain tests provisioning a node correctly the first time: package or tarball install, cassandra.yaml settings, JVM and OS tuning, ports, and safe cluster admission. Install from tarball, Debian/RPM, or a supported image; run as a non-root cassandra user.
314 words, about 2 min03Data Modeling and CQL Schema Design
This domain tests query-first schema design in CQL: choosing partition keys that spread data, clustering columns that support required sort and range filters, and avoiding patterns Cassandra cannot serve efficiently. Start from the query.
329 words, about 2 min04Data Distribution: Partitioning, Replication, Consistency, and Topology
This domain tests how Cassandra places replicas across tokens, racks, and data centers, and how consistency levels trade latency against replica acknowledgement. SimpleStrategy is for single-DC or development only.
308 words, about 2 min05Performance Tuning: Compaction, Caching, Read/Write Path, and JVM
This domain tests tuning the storage engine and JVM: choosing a compaction strategy that matches workload, sizing caches, understanding the read/write path, and avoiding heap and GC pitfalls. SizeTieredCompactionStrategy is write-optimized but has high space amplification and temporary double-disk usage.
310 words, about 2 min06Repair, Backup, Restore, and Anti-Entropy
This domain tests anti-entropy and data protection: scheduling repair inside gc grace seconds, taking consistent snapshots, and restoring without corrupting topology. nodetool repair builds Merkle trees for token ranges and streams mismatched data.
346 words, about 2 min07Security: Authentication, Authorization, Encryption, and Audit
This domain tests locking down access: authentication, authorization, transport and internode encryption, and audit visibility. authenticator controls login.
300 words, about 2 min08Operations, Monitoring, Troubleshooting, and Upgrades
This domain tests day-two operations: reading nodetool and logs, diagnosing unavailable or latency issues, safely decommissioning or replacing nodes, and performing rolling upgrades. nodetool status shows UN for up/normal, DN for down/normal, UL for up/leaving, and UJ for up/joining.
343 words, about 2 min