All 7 Persistence (RDB/AOF) questions
More in Persistence (RDB/AOF)
What is AOF, or append only file, persistence, and how does it differ from RDB snapshots? What are the different appendfsync options available for AOF persistence, and how do they balance durability against performance? What is AOF rewriting, and why is it necessary as an append only file grows over time? What happens if Redis's persistence files, whether RDB or AOF, become corrupted, and how would you attempt to recover? How would you design a persistence strategy that combines both RDB and AOF to get the benefits of both approaches? What happens during Redis startup regarding data loading, and how does the choice between RDB and AOF affect startup time for a large dataset?
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Redis › Persistence (RDB/AOF)

What is RDB persistence in Redis, and how does it work?

Beginner

Answer

RDB persistence periodically saves a complete point in time snapshot of your entire dataset to a single compact file on disk, based on configured save rules, such as saving automatically if a certain number of changes have been made within a given time period, giving you a compact backup you can use to restore your data if Redis restarts.
SAVE -- creates an RDB snapshot immediately
BGSAVE -- creates a snapshot in the background
CONFIG SET save '900 1'
Real-world example A company configures Redis to automatically save an RDB snapshot every fifteen minutes if at least one key has changed, giving them a reasonably recent backup without needing to save constantly and impact performance.

Common follow-ups: What is the difference between SAVE and BGSAVE?;How much data could potentially be lost if Redis crashes right before a scheduled RDB save?

Redis Backup & Disaster Recovery;Redis Architecture & Installation
All 7 Persistence (RDB/AOF) questions