Backup generations terminology: in a grandfather–father–son rotation, the file created yesterday is commonly referred to as which generation?

Introduction / Context:
The grandfather–father–son (GFS) backup scheme labels backups by recency to simplify retention and restoration. Understanding these labels helps operators quickly identify which copy to use after a failure and how to rotate media for compliance and disaster recovery objectives.

Given Data / Assumptions:

• GFS uses three tiers: daily (son), weekly (father), monthly (grandfather), or analogous recency labels.
• “Yesterday” refers to the previous generation from “today’s” point-in-time.
• We use the conventional mapping of terms.

Concept / Approach:
In GFS, the son is the newest (today’s or most recent) backup. The father is the next older generation (commonly the prior day or prior week, depending on policy). The grandfather is the oldest retained tier (often monthly). Therefore, the file created yesterday is the father file in the rotation hierarchy.

Step-by-Step Solution:

Verification / Alternative check:
Operations runbooks and certification texts define GFS with son (most recent), father (previous), grandfather (oldest cycle), confirming the labeling.

Why Other Options Are Wrong:

• Son: Today’s newest, not yesterday’s.
• Grandfather: Typically monthly/oldest, not just one day old.
• Mother: Not a term used in GFS.
• None: Incorrect because “father” is standard.

Common Pitfalls:
Confusing day/week/month mappings; using nonstandard labels that hinder recovery teams.

Final Answer:
"father" file