diff --git a/scripts/smoke/seed-abcip-smoke.sql b/scripts/smoke/seed-abcip-smoke.sql
index f9c9e4d..14028cb 100644
--- a/scripts/smoke/seed-abcip-smoke.sql
+++ b/scripts/smoke/seed-abcip-smoke.sql
@@ -47,12 +47,14 @@ DELETE FROM dbo.ClusterNodeGenerationState WHERE NodeId = @NodeId;
 DELETE FROM dbo.ClusterNode                WHERE NodeId = @NodeId;
 DELETE FROM dbo.ServerCluster              WHERE ClusterId = @ClusterId;
 
+DELETE FROM dbo.ClusterNodeCredential WHERE Kind = 'SqlLogin' AND Value = 'sa';
+
 INSERT dbo.ServerCluster(ClusterId, Name, Enterprise, Site, NodeCount, RedundancyMode, Enabled, CreatedBy)
 VALUES (@ClusterId, 'AB CIP Smoke', 'zb', 'lab', 1, 'None', 1, 'abcip-smoke');
 
 INSERT dbo.ClusterNode(NodeId, ClusterId, RedundancyRole, Host, OpcUaPort, DashboardPort,
                        ApplicationUri, ServiceLevelBase, Enabled, CreatedBy)
-VALUES (@NodeId, @ClusterId, 'Primary', 'localhost', 4840, 5000,
+VALUES (@NodeId, @ClusterId, 'Primary', 'localhost', 4840, 15050,
         'urn:OtOpcUa:abcip-smoke-node', 200, 1, 'abcip-smoke');
 
 INSERT dbo.ClusterNodeCredential(NodeId, Kind, Value, Enabled, CreatedBy)
diff --git a/scripts/smoke/seed-ablegacy-smoke.sql b/scripts/smoke/seed-ablegacy-smoke.sql
index 1da13d1..2ce007f 100644
--- a/scripts/smoke/seed-ablegacy-smoke.sql
+++ b/scripts/smoke/seed-ablegacy-smoke.sql
@@ -44,12 +44,14 @@ DELETE FROM dbo.ClusterNodeGenerationState WHERE NodeId = @NodeId;
 DELETE FROM dbo.ClusterNode                WHERE NodeId = @NodeId;
 DELETE FROM dbo.ServerCluster              WHERE ClusterId = @ClusterId;
 
+DELETE FROM dbo.ClusterNodeCredential WHERE Kind = 'SqlLogin' AND Value = 'sa';
+
 INSERT dbo.ServerCluster(ClusterId, Name, Enterprise, Site, NodeCount, RedundancyMode, Enabled, CreatedBy)
 VALUES (@ClusterId, 'AB Legacy Smoke', 'zb', 'lab', 1, 'None', 1, 'ablegacy-smoke');
 
 INSERT dbo.ClusterNode(NodeId, ClusterId, RedundancyRole, Host, OpcUaPort, DashboardPort,
                        ApplicationUri, ServiceLevelBase, Enabled, CreatedBy)
-VALUES (@NodeId, @ClusterId, 'Primary', 'localhost', 4840, 5000,
+VALUES (@NodeId, @ClusterId, 'Primary', 'localhost', 4840, 15050,
         'urn:OtOpcUa:ablegacy-smoke-node', 200, 1, 'ablegacy-smoke');
 
 INSERT dbo.ClusterNodeCredential(NodeId, Kind, Value, Enabled, CreatedBy)
diff --git a/scripts/smoke/seed-modbus-smoke.sql b/scripts/smoke/seed-modbus-smoke.sql
index a2be86d..dcaa91c 100644
--- a/scripts/smoke/seed-modbus-smoke.sql
+++ b/scripts/smoke/seed-modbus-smoke.sql
@@ -56,13 +56,22 @@ DELETE FROM dbo.ClusterNodeGenerationState WHERE NodeId = @NodeId;
 DELETE FROM dbo.ClusterNode                WHERE NodeId = @NodeId;
 DELETE FROM dbo.ServerCluster              WHERE ClusterId = @ClusterId;
 
+-- `UX_ClusterNodeCredential_Value` is a unique index on (Kind, Value) WHERE
+-- Enabled=1, so a `sa` login can only bind to one node at a time. Drop any
+-- prior smoke cluster's binding before we claim the login for this one.
+DELETE FROM dbo.ClusterNodeCredential WHERE Kind = 'SqlLogin' AND Value = 'sa';
+
 -- 1. Cluster + Node.
 INSERT dbo.ServerCluster(ClusterId, Name, Enterprise, Site, NodeCount, RedundancyMode, Enabled, CreatedBy)
 VALUES (@ClusterId, 'Modbus Smoke', 'zb', 'lab', 1, 'None', 1, 'modbus-smoke');
 
+-- DashboardPort 15050 rather than 5000 — HttpListener on :5000 requires
+-- URL-ACL reservation or admin rights on Windows (HttpListenerException 32).
+-- 15000+ ports are unreserved by default. Safe to change back when deploying
+-- with a netsh urlacl grant or reverse-proxy fronting :5000.
 INSERT dbo.ClusterNode(NodeId, ClusterId, RedundancyRole, Host, OpcUaPort, DashboardPort,
                        ApplicationUri, ServiceLevelBase, Enabled, CreatedBy)
-VALUES (@NodeId, @ClusterId, 'Primary', 'localhost', 4840, 5000,
+VALUES (@NodeId, @ClusterId, 'Primary', 'localhost', 4840, 15050,
         'urn:OtOpcUa:modbus-smoke-node', 200, 1, 'modbus-smoke');
 
 -- Bind the SQL login this smoke test connects as to the node identity. The
diff --git a/scripts/smoke/seed-s7-smoke.sql b/scripts/smoke/seed-s7-smoke.sql
index 6a0e723..98868ee 100644
--- a/scripts/smoke/seed-s7-smoke.sql
+++ b/scripts/smoke/seed-s7-smoke.sql
@@ -48,13 +48,16 @@ DELETE FROM dbo.ClusterNodeGenerationState WHERE NodeId = @NodeId;
 DELETE FROM dbo.ClusterNode                WHERE NodeId = @NodeId;
 DELETE FROM dbo.ServerCluster              WHERE ClusterId = @ClusterId;
 
+DELETE FROM dbo.ClusterNodeCredential WHERE Kind = 'SqlLogin' AND Value = 'sa';
+
 INSERT dbo.ServerCluster(ClusterId, Name, Enterprise, Site, NodeCount, RedundancyMode, Enabled, CreatedBy)
 VALUES (@ClusterId, 'S7 Smoke', 'zb', 'lab', 1, 'None', 1, 's7-smoke');
 
 INSERT dbo.ClusterNode(NodeId, ClusterId, RedundancyRole, Host, OpcUaPort, DashboardPort,
                        ApplicationUri, ServiceLevelBase, Enabled, CreatedBy)
-VALUES (@NodeId, @ClusterId, 'Primary', 'localhost', 4840, 5000,
+VALUES (@NodeId, @ClusterId, 'Primary', 'localhost', 4840, 15050,
         'urn:OtOpcUa:s7-smoke-node', 200, 1, 's7-smoke');
+-- Dashboard moved off :5000 (Windows URL-ACL).
 
 INSERT dbo.ClusterNodeCredential(NodeId, Kind, Value, Enabled, CreatedBy)
 VALUES (@NodeId, 'SqlLogin', 'sa', 1, 's7-smoke');