diff --git a/test/openpower-pels/Makefile.include b/test/openpower-pels/Makefile.include
index d85f215..2ce9498 100644
--- a/test/openpower-pels/Makefile.include
+++ b/test/openpower-pels/Makefile.include
@@ -8,6 +8,7 @@
 	failing_mtms_test \
 	fru_identity_test \
 	generic_section_test \
+	host_notifier_test \
 	log_id_test \
 	mru_test \
 	mtms_test \
@@ -145,6 +146,7 @@
 	$(test_ldadd) \
 	$(pel_objects) \
 	$(top_builddir)/extensions/openpower-pels/data_interface.o \
+	$(top_builddir)/extensions/openpower-pels/host_notifier.o \
 	$(top_builddir)/extensions/openpower-pels/manager.o \
 	$(top_builddir)/extensions/openpower-pels/repository.o
 pel_manager_test_LDFLAGS = $(test_ldflags)
@@ -316,3 +318,16 @@
 	$(test_ldflags) \
 	$(top_builddir)/extensions/openpower-pels/pel_rules.o
 pel_rules_test_LDFLAGS = $(test_ldflags)
+
+host_notifier_test_SOURCES = \
+	%reldir%/host_notifier_test.cpp \
+	%reldir%/paths.cpp \
+	%reldir%/pel_utils.cpp
+host_notifier_test_CPPFLAGS = $(test_cppflags)
+host_notifier_test_CXXFLAGS = $(test_cxxflags) $(SDEVENTPLUS_CFLAGS)
+host_notifier_test_LDADD = \
+	$(test_ldflags) \
+	$(pel_objects) \
+	$(top_builddir)/extensions/openpower-pels/host_notifier.o \
+	$(top_builddir)/extensions/openpower-pels/repository.o
+host_notifier_test_LDFLAGS = $(test_ldflags) $(SDEVENTPLUS_LIBS)
diff --git a/test/openpower-pels/host_notifier_test.cpp b/test/openpower-pels/host_notifier_test.cpp
new file mode 100644
index 0000000..2d50dcf
--- /dev/null
+++ b/test/openpower-pels/host_notifier_test.cpp
@@ -0,0 +1,135 @@
+/**
+ * Copyright © 2019 IBM Corporation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+#include "extensions/openpower-pels/data_interface.hpp"
+#include "extensions/openpower-pels/host_notifier.hpp"
+#include "mocks.hpp"
+#include "pel_utils.hpp"
+
+#include <fcntl.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+
+#include <chrono>
+
+#include <gtest/gtest.h>
+
+using namespace openpower::pels;
+using ::testing::_;
+using ::testing::Invoke;
+using ::testing::Return;
+namespace fs = std::filesystem;
+using namespace std::chrono;
+
+const size_t actionFlags0Offset = 66;
+const size_t actionFlags1Offset = 67;
+
+class HostNotifierTest : public CleanPELFiles
+{
+};
+
+/**
+ * @brief Create PEL with the specified action flags
+ *
+ * @param[in] actionFlagsMask - Optional action flags to use
+ *
+ * @return std::unique_ptr<PEL>
+ */
+std::unique_ptr<PEL> makePEL(uint16_t actionFlagsMask = 0)
+{
+    static uint32_t obmcID = 1;
+    auto data = pelDataFactory(TestPELType::pelSimple);
+
+    data[actionFlags0Offset] |= actionFlagsMask >> 8;
+    data[actionFlags1Offset] |= actionFlagsMask & 0xFF;
+
+    auto pel = std::make_unique<PEL>(data, obmcID++);
+    pel->assignID();
+    pel->setCommitTime();
+    return pel;
+}
+
+// Test that host state change callbacks work
+TEST_F(HostNotifierTest, TestHostStateChange)
+{
+    MockDataInterface dataIface;
+
+    bool hostState = false;
+    bool called = false;
+    DataInterfaceBase::HostStateChangeFunc func = [&hostState,
+                                                   &called](bool state) {
+        hostState = state;
+        called = true;
+    };
+
+    dataIface.subscribeToHostStateChange("test", func);
+
+    // callback called
+    dataIface.changeHostState(true);
+    EXPECT_TRUE(called);
+    EXPECT_TRUE(hostState);
+
+    // No change, not called
+    called = false;
+    dataIface.changeHostState(true);
+    EXPECT_FALSE(called);
+
+    // Called again
+    dataIface.changeHostState(false);
+    EXPECT_FALSE(hostState);
+    EXPECT_TRUE(called);
+
+    // Shouldn't get called after an unsubscribe
+    dataIface.unsubscribeFromHostStateChange("test");
+
+    called = false;
+
+    dataIface.changeHostState(true);
+    EXPECT_FALSE(called);
+}
+
+// Test that PELs are enqueued on startup
+TEST_F(HostNotifierTest, TestStartup)
+{
+    Repository repo{repoPath};
+    MockDataInterface dataIface;
+
+    // Give the repo 10 PELs to start with
+    for (int i = 0; i < 10; i++)
+    {
+        auto pel = makePEL();
+        repo.add(pel);
+    }
+
+    sd_event* event = nullptr;
+    auto r = sd_event_default(&event);
+    ASSERT_TRUE(r >= 0);
+
+    std::unique_ptr<HostInterface> hostIface =
+        std::make_unique<MockHostInterface>(event, dataIface);
+
+    HostNotifier notifier{repo, dataIface, std::move(hostIface)};
+
+    ASSERT_EQ(notifier.queueSize(), 10);
+
+    // Now add 10 more after the notifier is watching
+    for (int i = 0; i < 10; i++)
+    {
+        auto pel = makePEL();
+        repo.add(pel);
+    }
+
+    ASSERT_EQ(notifier.queueSize(), 20);
+}
diff --git a/test/openpower-pels/mocks.hpp b/test/openpower-pels/mocks.hpp
index 1dc0902..c2a84a0 100644
--- a/test/openpower-pels/mocks.hpp
+++ b/test/openpower-pels/mocks.hpp
@@ -1,4 +1,10 @@
 #include "extensions/openpower-pels/data_interface.hpp"
+#include "extensions/openpower-pels/host_interface.hpp"
+
+#include <fcntl.h>
+
+#include <filesystem>
+#include <sdeventplus/source/io.hpp>
 
 #include <gmock/gmock.h>
 
@@ -13,10 +19,53 @@
     MockDataInterface()
     {
     }
-    MOCK_CONST_METHOD0(getMachineTypeModel, std::string());
-    MOCK_CONST_METHOD0(getMachineSerialNumber, std::string());
-    MOCK_CONST_METHOD0(getServerFWVersion, std::string());
-    MOCK_CONST_METHOD0(getBMCFWVersion, std::string());
+    MOCK_METHOD(std::string, getMachineTypeModel, (), (const override));
+    MOCK_METHOD(std::string, getMachineSerialNumber, (), (const override));
+    MOCK_METHOD(std::string, getServerFWVersion, (), (const override));
+    MOCK_METHOD(std::string, getBMCFWVersion, (), (const override));
+
+    void changeHostState(bool newState)
+    {
+        setHostState(newState);
+    }
+
+    void setHMCManaged(bool managed)
+    {
+        _hmcManaged = managed;
+    }
+};
+
+/**
+ * @brief The mock HostInterface class
+ */
+class MockHostInterface : public HostInterface
+{
+  public:
+    MockHostInterface(sd_event* event, DataInterfaceBase& dataIface) :
+        HostInterface(event, dataIface)
+    {
+    }
+
+    virtual ~MockHostInterface()
+    {
+    }
+
+    virtual void cancelCmd() override
+    {
+    }
+
+    MOCK_METHOD(CmdStatus, sendNewLogCmd, (uint32_t, uint32_t), (override));
+
+  protected:
+    void receive(sdeventplus::source::IO& source, int fd,
+                 uint32_t events) override
+    {
+        // Keep account of the number of commands responses for testing.
+        _cmdsProcessed++;
+    }
+
+  private:
+    size_t _cmdsProcessed = 0;
 };
 
 } // namespace pels