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+# ─────────────────────────────────────────────────────────────────────────
+# postgresql/cutover/postgresql-ha-staging.yaml — ADR-0001 Phase 3, Stage 2
+#
+# Deployed by postgres-ha-cutover.sh as a SEPARATE stack:
+#   docker stack deploy -c postgresql/cutover/postgresql-ha-staging.yaml postgresqlha
+#
+# ⚠️  NEVER deploy this via stack-deploy.sh or under the "postgresql" stack
+#     name. It lives in cutover/ (a subdirectory) deliberately:
+#     stack-deploy.sh folder mode merges all *.yml/yaml at -maxdepth 1 of
+#     postgresql/, and merging this into the production stack would cause
+#     an outage. Subdirectory files are excluded from that merge.
+#
+# What this stage does:
+#   - Joins the EXISTING postgresql_db-backend overlay (external) — the
+#     live single-instance stack is untouched and keeps the "postgresql"
+#     and "db" aliases.
+#   - patroni-0/patroni-1 bootstrap a NEW cluster (scope: postgres-ha) by
+#     CLONING the live instance via pg_basebackup (CLONE_WITH_BASEBACKUP,
+#     CLONE_HOST=postgresql → resolves to the OLD instance during staging).
+#     CLONE_* is set on BOTH patroni nodes: whichever wins the initial
+#     leader race performs the clone; the other syncs from it.
+#   - HAProxy runs WITHOUT production aliases and WITHOUT published ports.
+#     It only gets those in postgresql-ha-final.yaml at promote time.
+#   - Superuser is PGadmin (matches the cloned data's existing superuser,
+#     same password secret), NOT Spilo's default "postgres".
+# ─────────────────────────────────────────────────────────────────────────
+version: "3.6"
+
+services:
+
+  etcd-1:
+    image: quay.io/coreos/etcd:v3.5.9
+    hostname: etcd-1
+    command:
+      - etcd
+      - --name=etcd-1
+      - --data-dir=/etcd-data
+      - --initial-advertise-peer-urls=http://etcd-1:2380
+      - --listen-peer-urls=http://0.0.0.0:2380
+      - --listen-client-urls=http://0.0.0.0:2379
+      - --advertise-client-urls=http://etcd-1:2379
+      - --initial-cluster=etcd-1=http://etcd-1:2380,etcd-2=http://etcd-2:2380,etcd-3=http://etcd-3:2380
+      - --initial-cluster-state=new
+      - --initial-cluster-token=postgresql-ha-etcd
+    volumes:
+      - /volume1/docker/PostgreSQL/etcd-1-data:/etcd-data
+    networks:
+      - postgresql_db-backend
+    deploy:
+      placement:
+        constraints:
+          - node.hostname == docker-1
+
+  etcd-2:
+    image: quay.io/coreos/etcd:v3.5.9
+    hostname: etcd-2
+    command:
+      - etcd
+      - --name=etcd-2
+      - --data-dir=/etcd-data
+      - --initial-advertise-peer-urls=http://etcd-2:2380
+      - --listen-peer-urls=http://0.0.0.0:2380
+      - --listen-client-urls=http://0.0.0.0:2379
+      - --advertise-client-urls=http://etcd-2:2379
+      - --initial-cluster=etcd-1=http://etcd-1:2380,etcd-2=http://etcd-2:2380,etcd-3=http://etcd-3:2380
+      - --initial-cluster-state=new
+      - --initial-cluster-token=postgresql-ha-etcd
+    volumes:
+      - /volume1/docker/PostgreSQL/etcd-2-data:/etcd-data
+    networks:
+      - postgresql_db-backend
+    deploy:
+      placement:
+        constraints:
+          - node.hostname == docker-2
+
+  etcd-3:
+    image: quay.io/coreos/etcd:v3.5.9
+    hostname: etcd-3
+    command:
+      - etcd
+      - --name=etcd-3
+      - --data-dir=/etcd-data
+      - --initial-advertise-peer-urls=http://etcd-3:2380
+      - --listen-peer-urls=http://0.0.0.0:2380
+      - --listen-client-urls=http://0.0.0.0:2379
+      - --advertise-client-urls=http://etcd-3:2379
+      - --initial-cluster=etcd-1=http://etcd-1:2380,etcd-2=http://etcd-2:2380,etcd-3=http://etcd-3:2380
+      - --initial-cluster-state=new
+      - --initial-cluster-token=postgresql-ha-etcd
+    volumes:
+      - /volume1/docker/PostgreSQL/etcd-3-data:/etcd-data
+    networks:
+      - postgresql_db-backend
+    deploy:
+      placement:
+        constraints:
+          - node.hostname == docker-3
+
+  patroni-0:
+    image: ghcr.io/zalando/spilo-17:4.0-p3
+    hostname: patroni-0
+    command:
+      - /bin/sh
+      - -c
+      - |
+        export PGPASSWORD_SUPERUSER="$(cat /run/secrets/postgresql_password)"
+        export PGPASSWORD_STANDBY="$(cat /run/secrets/postgresql_replication_password)"
+        export PATRONI_RESTAPI_PASSWORD="$(cat /run/secrets/postgresql_patroni_password)"
+        export CLONE_PASSWORD="$(cat /run/secrets/postgresql_password)"
+        exec /bin/sh /launch.sh init
+    environment:
+      SCOPE: postgres-ha
+      PATRONI_NAME: patroni-0
+      ETCD_HOSTS: '"etcd-1:2379","etcd-2:2379","etcd-3:2379"'
+      PGUSER_SUPERUSER: PGadmin
+      PGUSER_STANDBY: standby
+      PATRONI_RESTAPI_USERNAME: patroni
+      PGROOT: /home/postgres/pgdata/pgroot
+      # Clone-from-live: only runs when PGDATA is empty (first bootstrap).
+      # "postgresql" resolves to the OLD single instance during staging.
+      CLONE_METHOD: CLONE_WITH_BASEBACKUP
+      CLONE_SCOPE: legacy-single
+      CLONE_HOST: postgresql
+      CLONE_PORT: "5432"
+      CLONE_USER: PGadmin
+    secrets:
+      - postgresql_password
+      - postgresql_replication_password
+      - postgresql_patroni_password
+    volumes:
+      - /volume1/docker/PostgreSQL/patroni-0-data:/home/postgres/pgdata
+    networks:
+      - postgresql_db-backend
+    deploy:
+      placement:
+        constraints:
+          - node.labels.pg-role == primary
+
+  patroni-1:
+    image: ghcr.io/zalando/spilo-17:4.0-p3
+    hostname: patroni-1
+    command:
+      - /bin/sh
+      - -c
+      - |
+        export PGPASSWORD_SUPERUSER="$(cat /run/secrets/postgresql_password)"
+        export PGPASSWORD_STANDBY="$(cat /run/secrets/postgresql_replication_password)"
+        export PATRONI_RESTAPI_PASSWORD="$(cat /run/secrets/postgresql_patroni_password)"
+        export CLONE_PASSWORD="$(cat /run/secrets/postgresql_password)"
+        exec /bin/sh /launch.sh init
+    environment:
+      SCOPE: postgres-ha
+      PATRONI_NAME: patroni-1
+      ETCD_HOSTS: '"etcd-1:2379","etcd-2:2379","etcd-3:2379"'
+      PGUSER_SUPERUSER: PGadmin
+      PGUSER_STANDBY: standby
+      PATRONI_RESTAPI_USERNAME: patroni
+      PGROOT: /home/postgres/pgdata/pgroot
+      CLONE_METHOD: CLONE_WITH_BASEBACKUP
+      CLONE_SCOPE: legacy-single
+      CLONE_HOST: postgresql
+      CLONE_PORT: "5432"
+      CLONE_USER: PGadmin
+    secrets:
+      - postgresql_password
+      - postgresql_replication_password
+      - postgresql_patroni_password
+    volumes:
+      - /volume1/docker/PostgreSQL/patroni-1-data:/home/postgres/pgdata
+    networks:
+      - postgresql_db-backend
+    deploy:
+      placement:
+        constraints:
+          - node.labels.pg-role == replica
+
+  # Staging HAProxy: NO production aliases, NO published ports. Reachable
+  # in-network as "haproxy" for pre-promote testing only.
+  haproxy:
+    image: haproxy:2.9-alpine
+    hostname: haproxy
+    volumes:
+      - /volume1/docker/compose-files/postgresql/haproxy.cfg:/usr/local/etc/haproxy/haproxy.cfg:ro
+    networks:
+      - postgresql_db-backend
+    deploy:
+      mode: global
+
+networks:
+  postgresql_db-backend:
+    external: true
+
+secrets:
+  postgresql_password:
+    external: true
+  postgresql_replication_password:
+    external: true
+  postgresql_patroni_password:
+    external: true