0-2-2-understand-replica-synchronization

name	0.2.2-understand-replica_synchronization
description	[0.2.2] Propagation of updates to ensure all replicas converge toward identical state.

understand-replica_synchronization

CALL NUMBER: deep_consensus.replica_synchronization : distributed_consensus_and_replication_protocols(8) DEFINITION: Propagation of updates to ensure all replicas converge toward identical state.

Invoke this skill to understand replica_synchronization down to its primitives. The RELATIVE ROOT below is the least-fixed-point closure of everything it bundles from — the full import cone, grouped by the lib each prim comes from. Projected from a prover-typed KB (MAP/SWI-Prolog consistency gate): every reference below resolves.

THE RELATIVE ROOT (the import cone, by lib)

from deep_consensus

• gossip_dissemination (d1): Probabilistic epidemic protocol spreading updates through pairwise exchanges.
• view_change (d6): Transition of consensus membership to new configuration after membership modification.

from distributed_consensus_and_replication_protocols

• anti_entropy (d1): Repair of divergent replicas by comparing Merkle trees and exchanging differences.
• read_repair (d1): Background correction of stale replicas when read reveals outdated data.
• state_transfer (d2): Sending full current state to a lagging replica for rapid catch-up.
• eventual_consistency (d2): Given no new updates, all replicas will eventually converge to the same value.
• catch_up_recovery (d3): Process of syncing a lagging or new replica with current leader state.
• reconfiguration (d4): Process of changing cluster membership while maintaining consistency guarantees.
• membership_change (d5): Adding or removing nodes from the cluster without service interruption.
• joint_consensus (d6): Raft's two-phase configuration change using joint configuration of old and new members.

CONSUMERS (what needs this)

primary_backup, state_machine_replication

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Projected from the distributed consensus and replication protocols KB (196 concepts / 187 relations) — consistency-typed by MAP; the facet list after the colon IS the cross-lib dependency web.

(leaf — this is an actual skill.)