Answer
Rollback happens when a primary steps down before its oplog entries replicate. The node removes unreplicated writes on restart to match the majority view.
Quick Answer
Replication rollback occurs when a primary fails, a new primary is elected, and the old primary rejoins with writes that were never replicated to the majority. Those writes are rolled back (written to a rollback folder for manual recovery). To prevent rollback: use write concern majority. With w:1 writes, any unacknowledged write not yet replicated to the new primary is lost.
S
SugharaIQ Editorial Team
Verified Answer
This answer has been peer-reviewed by industry experts holding senior engineering roles to ensure technical accuracy and relevance for modern interview standards.
Want to bookmark, take notes, or join discussions?
Sign in to access all features and personalize your learning experience.
Source: SugharaIQ