diff --git a/checksums/SHA256SUMS b/checksums/SHA256SUMS
index c1e207a..695e3a9 100644
--- a/checksums/SHA256SUMS
+++ b/checksums/SHA256SUMS
@@ -7,7 +7,7 @@ bcfde96b98f4727a8c97d42a39b7c6ec925b1b89d17ef67cc58eb7bd67afbfae  ocf/loxthelion
 957a5a72ed277d0216e070abb80733483be3d421b9fa488e27fdd75bb2919548  ocf/loxthelion/managed-container.d/applications/postgresql/peer_config.sh
 99bb3478931eced9471a8f054c14d152780aec73801449d1a6b2f09a4b656bec  ocf/loxthelion/managed-container.d/applications/postgresql/plugin.sh
 c1d878dabf22ad3928d66a5542bda3c150e5e9b039926629e7c5fd3401d29be4  ocf/loxthelion/managed-container.d/applications/postgresql/postgres.sh
-f482853a0c7992981e59b4ad78d1ee69851d5d60fdec1f695673228017dd8244  ocf/loxthelion/managed-container.d/applications/postgresql/promote.sh
+78b32fd6354bec61375ee73a31898059b21d51949a906cc6c7f23419a79670d6  ocf/loxthelion/managed-container.d/applications/postgresql/promote.sh
 5166fc3370f49ab14cd975ded4b03a74b9bd7dbff5762b41a15552c42f934ea7  ocf/loxthelion/managed-container.d/applications/postgresql/promotion_state.py
 b0ebad749ed736f08ec748a693f12e8dc2541430e0d3db75bbb6b2b7e517f84b  ocf/loxthelion/managed-container.d/applications/postgresql/rejoin.sh
 0d3017fdca92b2dc5dba406065bc269622ce5140e3fce4a959ca95ce4a78e755  ocf/loxthelion/managed-container.d/applications/postgresql/replication.sh
@@ -23,13 +23,14 @@ a42bb59a058ffeb59c1baa96e403856910bbbaea98f9104ff93daf4b5970c780  postgres-host/
 957a5a72ed277d0216e070abb80733483be3d421b9fa488e27fdd75bb2919548  postgres-host/postgres-ha-peer-config.sh
 deb09e3ae40629f43b262ba4f9a7ebf59a1dca3da9d8c94478f670aea28bd0e1  quadlet/postgres.container
 04a125068677bbee6e71d313ca9d95d35faa32851b79de781cd7b9f466561445  quadlet/postgres.env.example
-a4bedb1c423294e4cafe4c93e9daff3d2b774a8f8e4a6b989322acbc2b842a04  tests/run-all.sh
+ac72a62381a686dbc7dcebf2f81bd3f96e84e83ba63ff956440546a8026037fb  tests/run-all.sh
 a373c0560391a2d8f63c3ba31609ab16b219d9b532b4ab9f8aea6dc45de10555  tests/test-demote-database-gate.sh
 688eeb756c7f346e7e55acc555004ba12b48bc7c3d309073658d5e84a6e5e348  tests/test-demote-database-parameter.sh
 22d3eb56e8cd3ae1a58e2616f44abd3818f79d7e5df55c1c158e36dca7c77f42  tests/test-demote-database-shadow.sh
 5e5d4fdd2b6c7e0b8b146de7aad06c1f96b221a10fec525b00d40e0d85709fb0  tests/test-entrypoint-structure.sh
 2faee72cf2fdcbfa667c3e1c2a7aabc053b96a9b8127ff7440ddb717fd2dc314  tests/test-notify-daemon-shadow.sh
 9150004af86a819d7d1b5ae2b3fa9d4ddd0480f55babd094137052109864b057  tests/test-notify-target-shadow.sh
+dd7ad3d1c06cac922c026b6bc30db5a5e66aa5d82948ebed983384c7b0bbba33  tests/test-promote-database-shadow.sh
 b83f0415c09f0be34c51722370e5b07c51b9a9756d305d3b3f50827f484aa4dd  tests/test-proxy-client-actions.py
 cc4482d229805c64d7df258a8a82984f244128d27fff4ea43b36caa004b56bef  tests/test-proxy-client-parameters.py
 c3b988d7b2b1b138bb2530df9172f96bb0f5edc2f1561f38f0055695f4126134  tests/test-proxy-protocol.sh
diff --git a/ocf/loxthelion/managed-container.d/applications/postgresql/promote.sh b/ocf/loxthelion/managed-container.d/applications/postgresql/promote.sh
index 0068a6f..a38b57e 100644
--- a/ocf/loxthelion/managed-container.d/applications/postgresql/promote.sh
+++ b/ocf/loxthelion/managed-container.d/applications/postgresql/promote.sh
@@ -1,5 +1,63 @@
 # Sourced by managed-container; uses the shared OCF and parameter environment.
 
+mc_pg_promote_database_shadow()
+{
+    local socket_path resource response rc
+
+    socket_path="${MC_PROXY_SOCKET:-/run/user/1000/managed-containerd/managed-containerd.sock}"
+    resource="${OCF_RESOURCE_INSTANCE:-}"
+    resource="${resource%%:*}"
+
+    # Standalone/resource-agent tests may not have a real resource identity.
+    [ -n "${resource}" ] || return 0
+
+    if response="$(
+        timeout --kill-after=1s 5s \
+            python3 \
+            "${MC_PROXY_CLIENT:-/usr/lib/ocf/resource.d/loxthelion/managed-container.d/proxy_client.py}" \
+            "${socket_path}" \
+            "${resource}" \
+            "promote.database" \
+            10 \
+            11
+    )"; then
+        rc=0
+    else
+        rc=$?
+    fi
+
+    if [ "${rc}" -ne 0 ]; then
+        ocf_log warn \
+            "managed-containerd promote.database shadow unavailable rc=${rc}"
+        return 0
+    fi
+
+    if MC_DAEMON_RESPONSE="${response}" python3 -c '
+import json
+import os
+
+response = json.loads(os.environ["MC_DAEMON_RESPONSE"])
+
+if (
+    response.get("ocf_rc") != 0
+    or response.get("ready") is not True
+    or response.get("mutation") is not False
+):
+    raise SystemExit(1)
+'; then
+        ocf_log info \
+            "managed-containerd promote.database shadow: comparison=MATCH response=${response}"
+    else
+        ocf_log err \
+            "managed-containerd promote.database shadow MISMATCH response=${response}"
+    fi
+
+    # Shadow-only milestone: daemon disagreement must not alter the
+    # authoritative native promotion result yet.
+    return 0
+}
+
+
 managed_promote()
 {
     local monitor_rc role i
@@ -58,6 +116,11 @@ managed_promote()
     ocf_log info \
         "Promoting PostgreSQL standby inside ${CONTAINER_NAME}"
 
+    # Independent managed-containerd promotion preflight.
+    # Shadow-only for now: disagreement is logged but does not block
+    # the authoritative native PostgreSQL promotion.
+    mc_pg_promote_database_shadow
+
     if ! pg_command '
         BINDIR="$(pg_config --bindir)" || exit 1
         exec "$BINDIR/pg_ctl" \
diff --git a/tests/run-all.sh b/tests/run-all.sh
index 175c6ed..cd8fc2d 100755
--- a/tests/run-all.sh
+++ b/tests/run-all.sh
@@ -27,6 +27,7 @@ python3 ./tests/test-proxy-client-parameters.py
 ./tests/test-notify-daemon-shadow.sh
 ./tests/test-notify-target-shadow.sh
 ./tests/test-demote-database-shadow.sh
+./tests/test-promote-database-shadow.sh
 ./tests/test-demote-database-gate.sh
 ./tests/test-demote-database-parameter.sh
 
diff --git a/tests/test-promote-database-shadow.sh b/tests/test-promote-database-shadow.sh
new file mode 100755
index 0000000..2c2d772
--- /dev/null
+++ b/tests/test-promote-database-shadow.sh
@@ -0,0 +1,30 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+ROOT="$(CDPATH= cd -- "$(dirname -- "$0")/.." && pwd)"
+FILE="$ROOT/ocf/loxthelion/managed-container.d/applications/postgresql/promote.sh"
+
+grep -q '^mc_pg_promote_database_shadow()' "$FILE"
+grep -q '"promote.database"' "$FILE"
+grep -q 'response.get("ready") is not True' "$FILE"
+grep -q 'response.get("mutation") is not False' "$FILE"
+grep -q 'comparison=MATCH' "$FILE"
+grep -q 'promote.database shadow MISMATCH' "$FILE"
+
+SHADOW_LINE="$(
+    grep -n '^[[:space:]]*mc_pg_promote_database_shadow$' "$FILE" |
+    tail -1 |
+    cut -d: -f1
+)"
+
+PROMOTE_LINE="$(
+    grep -n 'exec "\$BINDIR/pg_ctl"' "$FILE" |
+    head -1 |
+    cut -d: -f1
+)"
+
+[ -n "$SHADOW_LINE" ]
+[ -n "$PROMOTE_LINE" ]
+[ "$SHADOW_LINE" -lt "$PROMOTE_LINE" ]
+
+echo "PROMOTE_DATABASE_SHADOW_TEST_PASS=1"