diff --git a/tests/Server/ZB.MOM.WW.OtOpcUa.Host.IntegrationTests/EquipmentNamespaceMaterializationTests.cs b/tests/Server/ZB.MOM.WW.OtOpcUa.Host.IntegrationTests/EquipmentNamespaceMaterializationTests.cs
index dd78d6087..824336829 100644
--- a/tests/Server/ZB.MOM.WW.OtOpcUa.Host.IntegrationTests/EquipmentNamespaceMaterializationTests.cs
+++ b/tests/Server/ZB.MOM.WW.OtOpcUa.Host.IntegrationTests/EquipmentNamespaceMaterializationTests.cs
@@ -85,7 +85,7 @@ public sealed class EquipmentNamespaceMaterializationTests
                 return true;
             }
             return false;
-        }, TwoNodeClusterHarness.DeploySealTimeout);
+        }, TwoNodeClusterHarness.DeploySealTimeout, () => DescribeDeploymentAsync(harness, deploymentId));
 
         var composition = DeploymentArtifact.ParseComposition(artifact);
 
@@ -182,7 +182,7 @@ public sealed class EquipmentNamespaceMaterializationTests
                 return true;
             }
             return false;
-        }, TwoNodeClusterHarness.DeploySealTimeout);
+        }, TwoNodeClusterHarness.DeploySealTimeout, () => DescribeDeploymentAsync(harness, deploymentId));
 
         await using (var db = await CreateDbAsync(harness))
         {
@@ -261,7 +261,8 @@ public sealed class EquipmentNamespaceMaterializationTests
         return await factory.CreateDbContextAsync();
     }
 
-    private static async Task WaitForAsync(Func<Task<bool>> condition, TimeSpan timeout)
+    private static async Task WaitForAsync(Func<Task<bool>> condition, TimeSpan timeout,
+        Func<Task<string>>? diagnose = null)
     {
         var deadline = DateTime.UtcNow + timeout;
         while (DateTime.UtcNow < deadline)
@@ -269,6 +270,29 @@ public sealed class EquipmentNamespaceMaterializationTests
             if (await condition()) return;
             await Task.Delay(200);
         }
-        throw new TimeoutException($"Condition not met within {timeout}");
+        throw new TimeoutException($"Condition not met within {timeout}"
+            + (diagnose is null ? "" : $"; state at timeout: {await diagnose()}"));
+    }
+
+    /// <summary>
+    ///     lmxopcua#843: the seal wait used to time out with a bare "Condition not met within 45s" (seen once at load
+    ///     average 140–280, 48 s against a normal 3 s). Report where the deploy stood — the deployment row, each node's
+    ///     per-node state, and both nodes' cluster views — so the next failure says whether it was a slow apply, a node
+    ///     that never received the dispatch (no ack, still Applying), or a failed apply.
+    /// </summary>
+    private static async Task<string> DescribeDeploymentAsync(TwoNodeClusterHarness harness, Guid deploymentId)
+    {
+        await using var db = await CreateDbAsync(harness);
+        var d = await db.Deployments.AsNoTracking().FirstOrDefaultAsync(x => x.DeploymentId == deploymentId);
+        var nodes = await db.NodeDeploymentStates.AsNoTracking()
+            .Where(s => s.DeploymentId == deploymentId).ToListAsync();
+        static string View(Akka.Actor.ActorSystem s) => string.Join(",",
+            Akka.Cluster.Cluster.Get(s).State.Members.Select(m => $"{m.Address.Port}:{m.Status}"))
+            + $" unreachable={Akka.Cluster.Cluster.Get(s).State.Unreachable.Count}";
+        return $"deployment={d?.Status.ToString() ?? "<missing>"} artifact={d?.ArtifactBlob.Length ?? 0}B "
+            + $"failure='{d?.FailureReason}' created={d?.CreatedAtUtc:O} now={DateTime.UtcNow:O}; "
+            + $"nodes=[{string.Join("; ", nodes.Select(n => $"{n.NodeId} {n.Status} started={n.StartedAtUtc:O} applied={n.AppliedAtUtc:O} failure='{n.FailureReason}'"))}] "
+            + $"(expected {harness.NodeANodeId}, {harness.NodeBNodeId}); "
+            + $"A view=[{View(harness.NodeASystem)}] B view=[{View(harness.NodeBSystem)}]";
     }
 }