diff --git a/hosts/idols-aquamarine/monitoring/alert_rules/node-exporter.yml b/hosts/idols-aquamarine/monitoring/alert_rules/node-exporter.yml
index b28f4f4b..481842c4 100644
--- a/hosts/idols-aquamarine/monitoring/alert_rules/node-exporter.yml
+++ b/hosts/idols-aquamarine/monitoring/alert_rules/node-exporter.yml
@@ -136,7 +136,9 @@ groups:
             }}\n  LABELS = {{ $labels }}"
 
       - alert: HostFilesystemDeviceError
-        expr: "node_filesystem_device_error == 1"
+        # node-exporter always flags containerd/docker sandbox shm bind mounts
+        # (tmpfs) as device errors, exclude this known false positive.
+        expr: 'node_filesystem_device_error{device!="shm"} == 1'
         for: 0m
         labels:
           severity: critical