diff --git a/app.py b/app.py
index cdcc24d..cb888c5 100644
--- a/app.py
+++ b/app.py
@@ -66,7 +66,7 @@ previous_cpu = None
 service_status_lock = threading.Lock()
 service_check_executor = ThreadPoolExecutor(max_workers=16)
 datastore_cache_lock = threading.Lock()
-datastore_cache = {"stored_at": 0.0, "snapshot": None}
+datastore_cache = {"stored_at": 0.0, "snapshot": None, "raid": None, "raid_at": 0.0}
 raid_log_state = None
 hardware_log_once = set()
 
@@ -322,6 +322,20 @@ def format_remaining_time(value):
         parts.append(f"{minutes} Min.")
     return " ".join(parts) or "< 1 Min."
 
+def smart_status(device):
+    if not SMART_ENABLED:
+        return "Nicht aktiviert"
+    if not shutil.which("smartctl"):
+        return "smartctl nicht installiert"
+    smart_device = device.replace("/dev/", f"{HOST_DEVICE_PATH.rstrip('/')}/", 1)
+    smart_output, smart_error = _read_command(["smartctl", "-H", smart_device], timeout=6, warn_on_nonzero=False)
+    if not re.search(r"(?:overall-health|Health Status|SMART support is)", smart_output, re.IGNORECASE):
+        sat_output, sat_error = _read_command(["smartctl", "-H", "-d", "sat", smart_device], timeout=6, warn_on_nonzero=False)
+        if sat_output:
+            smart_output, smart_error = sat_output, sat_error
+    health = re.search(r"(?:SMART overall-health self-assessment test result|SMART Health Status):\s*(.+)", smart_output, re.IGNORECASE)
+    return health.group(1).strip() if health else ("Fehler: " + smart_error.strip()[:80] if smart_error.strip() else "Nicht unterstützt")
+
 def raid_status():
     global raid_log_state
     mdstat, mdstat_error = "", ""
@@ -375,6 +389,9 @@ def raid_status():
         block_devices = {item.get("path") or f"/dev/{item.get('name')}": item for item in _flatten_lsblk(json.loads(lsblk_output).get("blockdevices", []))}
     except (ValueError, AttributeError):
         block_devices = {}
+    smart_futures = {}
+    if SMART_ENABLED and shutil.which("smartctl"):
+        smart_futures = {disk["device"]: service_check_executor.submit(smart_status, disk["device"]) for disk in devices}
     for disk in devices:
         info = block_devices.get(disk["device"], {})
         parent = re.sub(r"(p)?\d+$", "", disk["device"])
@@ -393,25 +410,15 @@ def raid_status():
         if not serial and serial_log_key not in hardware_log_once:
             log.warning("Keine Seriennummer für %s gefunden; Host-Controller stellt möglicherweise keine bereit", disk["device"])
             hardware_log_once.add(serial_log_key)
-        if SMART_ENABLED and shutil.which("smartctl"):
-            smart_device = disk["device"].replace("/dev/", f"{HOST_DEVICE_PATH.rstrip('/')}/", 1)
-            smart_output, smart_error = _read_command(["smartctl", "-H", smart_device], timeout=6, warn_on_nonzero=False)
-            if not re.search(r"(?:overall-health|Health Status|SMART support is)", smart_output, re.IGNORECASE):
-                sat_output, sat_error = _read_command(["smartctl", "-H", "-d", "sat", smart_device], timeout=6, warn_on_nonzero=False)
-                if sat_output:
-                    smart_output, smart_error = sat_output, sat_error
-            health = re.search(r"(?:SMART overall-health self-assessment test result|SMART Health Status):\s*(.+)", smart_output, re.IGNORECASE)
-            disk["smart"] = health.group(1).strip() if health else ("Fehler: " + smart_error.strip()[:80] if smart_error.strip() else "Nicht unterstützt")
+        if SMART_ENABLED:
+            disk["smart"] = smart_futures[disk["device"]].result() if disk["device"] in smart_futures else smart_status(disk["device"])
             smart_log_key = "smart:" + disk["device"]
-            if health and "smart-info:" + disk["device"] not in hardware_log_once:
-                log.info("SMART-Status %s: %s", disk["device"], disk["smart"])
+            if disk["smart"] == "PASSED" and "smart-info:" + disk["device"] not in hardware_log_once:
+                log.info("SMART-Status %s: PASSED", disk["device"])
                 hardware_log_once.add("smart-info:" + disk["device"])
-            if not health and smart_log_key not in hardware_log_once:
+            elif disk["smart"] != "PASSED" and smart_log_key not in hardware_log_once:
                 log.warning("SMART-Status für %s nicht verfügbar: %s", disk["device"], disk["smart"])
                 hardware_log_once.add(smart_log_key)
-        elif SMART_ENABLED and "smartctl" not in hardware_log_once:
-            log.error("smartctl ist im Container nicht verfügbar; SMART kann nicht geprüft werden")
-            hardware_log_once.add("smartctl")
     missing = members_match and members_match.group(1) != members_match.group(2)
     failed = detail.get("failed_devices", 0) > 0 or any(disk["status"] == "failed" for disk in devices)
     rebuilding = bool(progress_match)
@@ -445,10 +452,25 @@ def datastore_snapshot():
     now = time.time()
     with datastore_cache_lock:
         if datastore_cache["snapshot"] is None or now - datastore_cache["stored_at"] >= max(30, STORAGE_CACHE_SECONDS):
-            datastore_cache["snapshot"] = scan_datastore_storage()
+            fresh_storage = scan_datastore_storage()
+            if fresh_storage.get("error") and datastore_cache["snapshot"]:
+                datastore_cache["snapshot"] = dict(datastore_cache["snapshot"])
+                datastore_cache["snapshot"]["stale"] = True
+                datastore_cache["snapshot"]["warning"] = fresh_storage["error"]
+            else:
+                datastore_cache["snapshot"] = fresh_storage
             datastore_cache["stored_at"] = now
         storage = datastore_cache["snapshot"]
-    return {"storage": storage, "raid": raid_status(), "cache_seconds": STORAGE_CACHE_SECONDS}
+    current_raid = raid_status()
+    with datastore_cache_lock:
+        if current_raid.get("status") == "failed" and current_raid.get("error") and datastore_cache.get("raid") and now - datastore_cache.get("raid_at", 0) < 60:
+            current_raid = dict(datastore_cache["raid"])
+            current_raid["stale"] = True
+            current_raid["warning"] = "Vorübergehend keine aktuelle RAID-Antwort; letzter gültiger Stand wird angezeigt."
+        elif current_raid.get("status") != "failed":
+            datastore_cache["raid"] = dict(current_raid)
+            datastore_cache["raid_at"] = now
+    return {"storage": storage, "raid": current_raid, "cache_seconds": STORAGE_CACHE_SECONDS}
 
 def cpu_usage_percent():
     global previous_cpu