Module replication 

Replication Module

Implements single-primary, multi-replica replication via WAL streaming.

Architecture

• Primary: accepts writes and streams WAL records to replicas
• Replica: read-only, connects to primary for WAL streaming
• Initial sync via snapshot transfer, then incremental WAL

Usage

// Primary
let options = RedDBOptions::persistent("./primary-data")
    .with_replication(ReplicationConfig::primary());

// Replica
let options = RedDBOptions::persistent("./replica-data")
    .with_replication(ReplicationConfig::replica("http://primary:55055"));

Re-exports

pub use cascade::plan_upstream;

pub use cascade::CascadeRefusal;

pub use cascade::CascadeRelay;

pub use cascade::CascadeUpstream;

pub use cascade::DownstreamSlot;

pub use cascade::ReplicaClass;

pub use cascade::UpstreamChoice;

pub use commit_policy::CommitPolicy;

pub use commit_waiter::AwaitOutcome;

pub use commit_waiter::CommitWaiter;

pub use control_plane::ControlPlaneConsensus;

pub use control_plane::ControlPlaneEntry;

pub use control_plane::ControlPlaneEntryKind;

pub use control_plane::ControlPlaneLogIndex;

pub use control_plane::ControlPlanePayload;

pub use control_plane::ControlPlaneRole;

pub use control_plane::MemberId;

pub use control_plane::ProposeRefusal;

pub use election::quorum_threshold;

pub use election::randomized_election_timeout;

pub use election::ElectionCoordinator;

pub use election::ElectionOutcome;

pub use election::ElectionRequest;

pub use election::ElectionTransport;

pub use election::LastVote;

pub use election::LastVoteError;

pub use election::LastVoteStore;

pub use election::Member;

pub use election::MemberKind;

pub use election::MemoryLastVoteStore;

pub use election::RefusalReason;

pub use election::VoteDecision;

pub use election::VoteRequest;

pub use election::Voter;

pub use election::VotingState;

pub use failover::FailoverCoordinator;

pub use failover::FailoverError;

pub use failover::FailoverMode;

pub use failover::FailoverNode;

pub use failover::FailoverOutcome;

pub use failover::FailoverRequest;

pub use failover::FailoverTransport;

pub use failover::NodeRole;

pub use failover::RoleAssignment;

pub use fence::term_is_stale;

pub use fence::FenceBoundary;

pub use fence::FenceVerdict;

pub use fence::MemoryTermStore;

pub use fence::StaleTermFenced;

pub use fence::StaleTermRejection;

pub use fence::StreamHandshake;

pub use fence::TermFence;

pub use fence::TermStore;

pub use fence::TermStoreError;

pub use flow_control::Admission;

pub use flow_control::FlowController;

pub use lease::LeaseError;

pub use lease::LeaseStore;

pub use quorum::QuorumConfig;

pub use quorum::QuorumCoordinator;

pub use quorum::QuorumError;

pub use rollback::DivergentTail;

pub use rollback::RollbackCoordinator;

pub use rollback::RollbackError;

pub use rollback::RollbackEvent;

pub use rollback::RollbackOutcome;

pub use rollback::RollbackPlan;

pub use rollback::RollbackRequest;

pub use rollback::RollbackTransport;

pub use rollback::TailRecord;

pub use signal_plane::CatalogVersionHint;

pub use signal_plane::IntraClusterSignalBus;

pub use signal_plane::LivenessObservation;

pub use signal_plane::LivenessStatus;

pub use signal_plane::LoadBucket;

pub use signal_plane::LoadMetricSample;

pub use signal_plane::MemberHealthInput;

pub use signal_plane::ReceivedSignal;

pub use signal_plane::SharedSignalTransport;

pub use signal_plane::SignalFrame;

pub use signal_plane::SignalPlane;

pub use signal_plane::SignalPlaneLimits;

pub use signal_plane::SignalPlaneMessage;

pub use signal_plane::SignalPlaneMetrics;

pub use signal_plane::SignalPlaneSchedule;

pub use signal_plane::SignalTransportError;

pub use signal_plane::SimulatedSignalPlane;

pub use signal_plane::TopologyHint;

pub use signal_plane::TransportSignalPlane;

pub use swap_db::RebootstrapInProgress;

pub use swap_db::SwapDb;

pub use topology_advertiser::LagConfig;

pub use topology_advertiser::TopologyAdvertiser;

pub use topology_advertiser::TopologyAuthGate;

pub use topology_advertiser::DEFAULT_REPLICA_TIMEOUT_MS;

pub use topology_advertiser::TOPOLOGY_READ_CAPABILITY;

pub use witness::RuntimeProfile;

pub use witness::WitnessSupervisor;

Modules

bookmark

Compatibility reexport for causal bookmark wire tokens.

cascade

Cascading replication for async read-replicas (issue #838, PRD #819).

cdc

Change Data Capture (CDC) — stream of database change events.

commit_policy

Primary commit policies (PLAN.md Phase 11.4).

commit_waiter

Synchronous commit waiter (PLAN.md Phase 11.4 — ack_n).

control_plane

Control-plane consensus seam (issue #996, parent #987, ADR 0052).

dst

Deterministic simulation testing helpers for the replication control plane.

election

Term-based, quorum-gated automatic election (issue #834, PRD #819, ADR 0030).

failover

Coordinated zero-RPO failover (issue #833, PRD #819).

fence

Stale-term fencing for a returning ex-primary (issue #835, PRD #819, ADR 0030).

flow_control

Write-admission flow control keyed on in-quorum replica lag (issue #826).

lease

Serverless writer lease (PLAN.md Phase 5 / W6).

logical

Logical replication helpers shared by replica apply and point-in-time restore.

primary

Primary-side replication: WAL record production and snapshot serving.

quorum

Quorum-based commit coordination (Phase 2.6 multi-region PG parity).

reconnect

Primary↔replica reconnect telemetry (issue #1243, PRD #1237 Phase B).

replica

Replica-side replication: connects to primary, consumes WAL records.

rollback

Auto-rollback of a deposed primary to the common point (issue #840, PRD #819, ADR 0030).

scheduler

Backup Scheduler — automatic periodic snapshots with optional remote upload.

signal_plane

Signal-plane dissemination seam (issue #1842, parent #1832, ADR 0073).

swap_db

Stay-readable re-bootstrap with an atomic dataset swap (issue #837, PRD #819).

topology_advertiser

Server-side TopologyAdvertiser (issue #167).

witness

Witness runtime profile (issue #836, PRD #819, ADR 0030).

Structs

CausalBookmark

FailoverProfile

Tuned failover constants over the existing lease, health, and grace mechanisms.

FileLastVoteStore

FileTermStore

ReplicationConfig

Configuration for replication.

WriterLease

Enums

BookmarkDecodeError

FailoverProfileName

Named failover timing posture.

ReplicationRole

Role of this RedDB instance in a replication cluster.

Constants

DEFAULT_REPLICATION_TERM

DEFAULT_SLOT_IDLE_TIMEOUT_MS

DEFAULT_SLOT_RETENTION_MAX_LAG_LSN

SHIPPED_FAILOVER_PROFILES