Some Cassandra Interview Questions

These are the list of some important interview questions, that we can expect from an Interview.

1) Repairs in Cassandra

Scenario 1: Internal read repair

Scenario 2: Manual repair, by nodetool

Scenario 3: Read repair

2) Reads Path

Scenario 1: Application to cassandra, implies depending on the driver policy like DCAware,TokenAware etc. Query goes to Any node in the cluster called as co-ordinator node and is responsible for acknowledge of data back to client.

Scenario 2: Read Architecture in a node. Flows from row_cache, bloom_filter, Key_caches, Partition_summaries, Partiotion_index, sstables.

3) Write Path

Commit_log then the mem_table which is in memory table structure where data is sorted as per the table partiton.

4) Installation types

tar, rpm, aptitude

5) jvm tuning

heap configuration, garbage collection with jvm G1GC, Concurrent GC and how it works

6) Snitch and its types and their functionality

simplesnitch, gossip, ec2snitch etc.

7) memtable allocations.

off heap, on heap etc

8) Adding, Decommissioning, Removing nodes.

9) Comparisons in Datastax, Cassandra.

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