Zookeeper hard
ZK 3.5+ supports 'TTL Nodes'. How do they differ from Ephemeral Nodes?
- A Ephemeral nodes are tied to a Session. TTL nodes are persistent nodes that are automatically deleted after a specified time (in ms) if not modified/accessed, regardless of session status.
- B TTL nodes use less memory.
- C TTL nodes are encrypted.
- D Ephemeral nodes have a timer.
Answer: A. Ephemeral nodes are tied to a Session. TTL nodes are persistent nodes that are automatically deleted after a specified time (in ms) if not modified/accessed, regardless of session status.
Ephemeral nodes require an active TCP connection. TTL nodes are useful for things like 'offline jobs' where the job finishes and disconnects, but the status record should linger for 5 minutes.
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