diff --git a/packages/apps/redis/templates/redisfailover.yaml b/packages/apps/redis/templates/redisfailover.yaml
index 49de69379..26b8ca1c6 100644
--- a/packages/apps/redis/templates/redisfailover.yaml
+++ b/packages/apps/redis/templates/redisfailover.yaml
@@ -29,6 +29,11 @@ metadata:
     redis-failover.freshworks.com/operator-group: cozystack
 spec:
   sentinel:
+    # Pin the sentinel engine. The freshworks-oss operator's compiled-in default
+    # moved 6.2.6→7.2.4; the data pods run a deliberate versionMap image below,
+    # but the sentinels were on the old 6.2.6 default and must not silently jump
+    # on upgrade. Bump as a deliberate, separate change.
+    image: redis:6.2.6-alpine
     replicas: 3
     resources: {{- include "cozy-lib.resources.defaultingSanitize" (list .Values.resourcesPreset .Values.resources $) | nindent 6 }}
   redis:
diff --git a/packages/system/harbor/templates/redis.yaml b/packages/system/harbor/templates/redis.yaml
index 68e6d3fc7..74a384af8 100644
--- a/packages/system/harbor/templates/redis.yaml
+++ b/packages/system/harbor/templates/redis.yaml
@@ -20,6 +20,12 @@ metadata:
     redis-failover.freshworks.com/operator-group: cozystack
 spec:
   sentinel:
+    # Pin the engine. The freshworks-oss operator's compiled-in default moved
+    # 6.2.6→7.2.4 between forks, and an unpinned image would silently jump on
+    # upgrade — with no rollback path, since 7.x rewrites the on-disk format
+    # 6.2.6 refuses to load. Keep Harbor's Redis on the version it runs today;
+    # bump it as a deliberate, separate change.
+    image: redis:6.2.6-alpine
     replicas: 3
     resources:
       limits:
@@ -29,6 +35,9 @@ spec:
         cpu: 250m
         memory: 128Mi
   redis:
+    # Pin the engine (see the sentinel note above): an upgrade must not rewrite
+    # Harbor's dump.rdb into a 7.x format a platform rollback can no longer load.
+    image: redis:6.2.6-alpine
     replicas: {{ .Values.redis.replicas }}
     resources:
       limits: