diff --git a/fboss/agent/hw/test/HwSwitchEnsemble.cpp b/fboss/agent/hw/test/HwSwitchEnsemble.cpp
index cc1c9cace38db..190580fbfce52 100644
--- a/fboss/agent/hw/test/HwSwitchEnsemble.cpp
+++ b/fboss/agent/hw/test/HwSwitchEnsemble.cpp
@@ -407,7 +407,11 @@ void HwSwitchEnsemble::applyInitialConfig(const cfg::SwitchConfig& initCfg) {
   CHECK(haveFeature(HwSwitchEnsemble::LINKSCAN))
       << "Link scan feature must be enabled for exercising "
       << "applyInitialConfig";
+
   linkToggler_->applyInitialConfig(initCfg);
+  /* link togglers apply config with ports down and bring ports up differently
+   */
+  currentConfig_ = initCfg;
 }
 
 void HwSwitchEnsemble::linkStateChanged(
diff --git a/fboss/agent/hw/test/dataplane_tests/HwLoadBalancerTests.h b/fboss/agent/hw/test/dataplane_tests/HwLoadBalancerTests.h
index ba720606a7ea0..f47f0fb557d33 100644
--- a/fboss/agent/hw/test/dataplane_tests/HwLoadBalancerTests.h
+++ b/fboss/agent/hw/test/dataplane_tests/HwLoadBalancerTests.h
@@ -47,9 +47,18 @@ class HwLoadBalancerTest
       bool loopThroughFrontPanel = false,
       bool loadBalanceExpected = true,
       uint8_t deviation = 25) {
+    /* TODO: remove this hack.
+     * apply thrift config relies on sdk version in switch config to determine
+     * how to compute load balancer seeds. however sdk version is unavailable in
+     * hw tests unlike agent tests. remove this hack when hw tests can inject
+     * sdk version in thrift config.
+     */
+    auto lbConfig = loadBalancer;
+    auto seed = getHwSwitch()->generateDeterministicSeed(*lbConfig.id());
+    lbConfig.seed() = seed;
     Runner::runLoadBalanceTest(
         ecmpWidth,
-        loadBalancer,
+        lbConfig,
         weights,
         loopThroughFrontPanel,
         loadBalanceExpected,
@@ -63,9 +72,12 @@ class HwLoadBalancerTest
       bool loopThroughFrontPanel = false,
       bool loadBalanceExpected = true,
       uint8_t deviation = 25) {
+    auto lbConfig = loadBalancer;
+    auto seed = getHwSwitch()->generateDeterministicSeed(*lbConfig.id());
+    lbConfig.seed() = seed;
     Runner::runDynamicLoadBalanceTest(
         ecmpWidth,
-        loadBalancer,
+        lbConfig,
         weights,
         loopThroughFrontPanel,
         loadBalanceExpected,
diff --git a/fboss/agent/test/utils/EcmpDataPlaneTestUtil.cpp b/fboss/agent/test/utils/EcmpDataPlaneTestUtil.cpp
index 3dd8e637f99cf..d4ae05033e740 100644
--- a/fboss/agent/test/utils/EcmpDataPlaneTestUtil.cpp
+++ b/fboss/agent/test/utils/EcmpDataPlaneTestUtil.cpp
@@ -101,27 +101,25 @@ bool HwEcmpDataPlaneTestUtil<EcmpSetupHelperT>::isLoadBalanced(
 template <typename AddrT>
 void HwEcmpDataPlaneTestUtil<AddrT>::programLoadBalancer(
     const cfg::LoadBalancer& lb) {
+  if (ensemble_->getHwAsicTable()
+          ->getSwitchIDs(HwAsic::Feature::HASH_FIELDS_CUSTOMIZATION)
+          .empty()) {
+    return;
+  }
+  auto config = ensemble_->getCurrentConfig();
+  config.loadBalancers()->clear();
+  config.loadBalancers()->push_back(lb);
   if (ensemble_->isSai()) {
     // always program half lag hash for sai switches, see CS00012317640
-    ensemble_->applyNewState(
-        [this, lb](const std::shared_ptr<SwitchState>& state) {
-          return utility::addLoadBalancers(
-              ensemble_,
-              state,
-              {lb,
-               utility::getTrunkHalfHashConfig(
-                   *ensemble_->getHwAsicTable()->getHwAsic(SwitchID(0)))},
-              ensemble_->scopeResolver());
-        },
-        "program lb");
-  } else {
-    ensemble_->applyNewState(
-        [this, lb](const std::shared_ptr<SwitchState>& state) {
-          return utility::setLoadBalancer(
-              ensemble_, state, lb, ensemble_->scopeResolver());
-        },
-        "program lb");
+    auto switchIds = ensemble_->getHwAsicTable()->getSwitchIDs(
+        HwAsic::Feature::SAI_LAG_HASH);
+    if (!switchIds.empty()) {
+      config.loadBalancers()->push_back(utility::getTrunkHalfHashConfig(
+          *ensemble_->getHwAsicTable()->getHwAsic(*switchIds.begin())));
+    }
   }
+  XLOG(INFO) << "Programming load balancer: " << *lb.id();
+  ensemble_->applyNewConfig(config);
 }
 
 template <typename AddrT>
diff --git a/fboss/agent/test/utils/LoadBalancerTestRunner.h b/fboss/agent/test/utils/LoadBalancerTestRunner.h
index 0a21ae816c4fe..d3311a7ebe694 100644
--- a/fboss/agent/test/utils/LoadBalancerTestRunner.h
+++ b/fboss/agent/test/utils/LoadBalancerTestRunner.h
@@ -244,11 +244,7 @@ class HwLoadBalancerTestRunner {
         // verfiy the Dlb fail packets is zero
         EXPECT_EQ(l3EcmpDlbFailPackets, 0);
 
-        auto cfg = utility::onePortPerInterfaceConfig(
-            getEnsemble(), getMasterLogicalPortIds());
-        cfg.udfConfig() = utility::addUdfFlowletAclConfig();
-        // Add flowlet config to convert flowlet QUALITY to PER_PACKET_QUALITY
-        // run the load balance test and verify again
+        auto cfg = getEnsemble()->getCurrentConfig();
         utility::addFlowletConfigs(
             cfg,
             getMasterLogicalPortIds(),