diff --git a/src/bin/dhcp6/Makefile.am b/src/bin/dhcp6/Makefile.am
index 60e9d0f33cb084a704ea60c5eae58a2603c8da5c..8f0dd76f1240d885b15f25dabba9f8c090d15b40 100644
--- a/src/bin/dhcp6/Makefile.am
+++ b/src/bin/dhcp6/Makefile.am
@@ -3,7 +3,6 @@ SUBDIRS = . tests
 AM_CPPFLAGS = -I$(top_srcdir)/src/lib -I$(top_builddir)/src/lib
 AM_CPPFLAGS += -I$(top_srcdir)/src/bin -I$(top_builddir)/src/bin
 AM_CPPFLAGS += -I$(top_srcdir)/src/lib/cc -I$(top_builddir)/src/lib/cc
-AM_CPPFLAGS += -DTOP_BUILDDIR="\"$(top_builddir)\""
 AM_CPPFLAGS += $(BOOST_INCLUDES)
 
 AM_CXXFLAGS = $(B10_CXXFLAGS)
@@ -63,7 +62,7 @@ b10_dhcp6_SOURCES += bundy_controller.cc
 endif
 
 if CONFIG_BACKEND_JSON
-b10_dhcp6_SOURCES += jsonfile_controller.cc
+b10_dhcp6_SOURCES += kea_controller.cc
 endif
 
 nodist_b10_dhcp6_SOURCES = dhcp6_messages.h dhcp6_messages.cc
diff --git a/src/bin/dhcp6/ctrl_dhcp6_srv.h b/src/bin/dhcp6/ctrl_dhcp6_srv.h
index 632007a041eb07cf97b73727df2bf27e10afa311..c0a5a5709c4e13e9e07bf8d4cd442e650f8c43ff 100644
--- a/src/bin/dhcp6/ctrl_dhcp6_srv.h
+++ b/src/bin/dhcp6/ctrl_dhcp6_srv.h
@@ -54,7 +54,7 @@ public:
     /// *_backend.cc
     ///
     /// @return true if initialization was successful, false if it failed
-    bool init(const std::string& config_file);
+    void init(const std::string& config_file);
 
     /// @brief Performs cleanup, immediately before termination
     ///
diff --git a/src/bin/dhcp6/kea_controller.cc b/src/bin/dhcp6/kea_controller.cc
index 2196d23462358364c7257515c97b40b60a4c965d..7e42df9ede3e805beb1db9d7dac78c5afdcedfcb 100644
--- a/src/bin/dhcp6/kea_controller.cc
+++ b/src/bin/dhcp6/kea_controller.cc
@@ -48,7 +48,7 @@ using namespace std;
 namespace isc {
 namespace dhcp {
 
-bool
+void
 ControlledDhcpv6Srv::init(const std::string& file_name) {
     // This is a configuration backend implementation that reads the
     // configuration from a JSON file.
@@ -58,11 +58,13 @@ ControlledDhcpv6Srv::init(const std::string& file_name) {
     isc::data::ConstElementPtr result;
 
     // Basic sanity check: file name must not be empty.
-    if (file_name.empty()) {
-        isc_throw(BadValue, "JSON configuration file not specified");
-    }
-
     try {
+        if (file_name.empty()) {
+            // Basic sanity check: file name must not be empty.
+            isc_throw(BadValue, "JSON configuration file not specified. Please"
+                      "use -c command line option.");
+        }
+
         // Read contents of the file and parse it as JSON
         json = Element::fromJSONFile(file_name, true);
 
@@ -99,7 +101,7 @@ ControlledDhcpv6Srv::init(const std::string& file_name) {
         LOG_ERROR(dhcp6_logger, DHCP6_CONFIG_LOAD_FAIL)
             .arg("Configuration failed: Undefined result of configureDhcp6Server"
                  "() function after attempting to read " + file_name);
-        return (false);
+        return;
     }
 
     // Now check is the returned result is successful (rcode=0) or not
@@ -112,14 +114,12 @@ ControlledDhcpv6Srv::init(const std::string& file_name) {
             reason = string(" (") + comment->stringValue() + string(")");
         }
         LOG_ERROR(dhcp6_logger, DHCP6_CONFIG_LOAD_FAIL).arg(reason);
-        return (false);
+        isc_throw(BadValue, "Failed to apply configuration:" << reason);
     }
 
     // We don't need to call openActiveSockets() or startD2() as these
     // methods are called in processConfig() which is called by
     // processCommand("reload-config", ...)
-
-    return (true);
 }
 
 void ControlledDhcpv6Srv::cleanup() {
@@ -129,34 +129,14 @@ void ControlledDhcpv6Srv::cleanup() {
 /// This is a logger initialization for JSON file backend.
 /// For now, it's just setting log messages to be printed on stdout.
 /// @todo: Implement this properly (see #3427)
-void Daemon::loggerInit(const char* log_name, bool verbose, bool ) {
-    // This method configures logger. For now it is very simple.
-    // We'll make it more robust once we add support for JSON-based logging
-    // configuration.
-
-    using namespace isc::log;
-
-    Severity severity = b10LoggerSeverity(verbose ? isc::log::DEBUG : isc::log::INFO);
-
-    // Set a directory for creating lockfiles when running tests
-    // @todo: Find out why this is needed. Without this, the logger doesn't
-    // work.
-    setenv("B10_LOCKFILE_DIR_FROM_BUILD", TOP_BUILDDIR, 1);
-
-    // Initialize logging
-    initLogger(log_name, severity, isc::log::MAX_DEBUG_LEVEL, NULL);
-
-    // Now configure logger output to stdout.
-    /// @todo: Make this configurable as part of #3427.
-    LoggerSpecification spec(log_name, severity,
-                             b10LoggerDbglevel(isc::log::MAX_DEBUG_LEVEL));
-    OutputOption option;
-    option.destination = OutputOption::DEST_CONSOLE;
-    option.stream = OutputOption::STR_STDOUT;
-
-    spec.addOutputOption(option);
-    LoggerManager manager;
-    manager.process(spec);
+void Daemon::loggerInit(const char*, bool verbose, bool ) {
+
+    setenv("B10_LOCKFILE_DIR_FROM_BUILD", "/tmp", 1);
+    setenv("B10_LOGGER_ROOT", "kea", 0);
+    setenv("B10_LOGGER_SEVERITY", (verbose ? "DEBUG":"INFO"), 0);
+    setenv("B10_LOGGER_DBGLEVEL", "99", 0);
+    setenv("B10_LOGGER_DESTINATION",  "stdout", 0);
+    isc::log::initLogger();
 }
 
 };
diff --git a/src/bin/dhcp6/main.cc b/src/bin/dhcp6/main.cc
index 08740eb7324833aec7ee499f5a9f46aefa0a66f1..49c70ec319227d5c334a91adb649e94e8c1e52a9 100644
--- a/src/bin/dhcp6/main.cc
+++ b/src/bin/dhcp6/main.cc
@@ -105,7 +105,6 @@ main(int argc, char* argv[]) {
 
 
     int ret = EXIT_SUCCESS;
-    bool status = true;
     try {
         // Initialize logging.  If verbose, we'll use maximum verbosity.
         // If standalone is enabled, do not buffer initial log messages
@@ -123,8 +122,8 @@ main(int argc, char* argv[]) {
             try {
                 // Initialize the server, i.e. establish control session
                 // if BIND10 backend is used or read a configuration file
-                // 
-                status = server.init(config_file);
+                server.init(config_file);
+
             } catch (const std::exception& ex) {
                 LOG_ERROR(dhcp6_logger, DHCP6_INIT_FAIL).arg(ex.what());
 
@@ -139,9 +138,6 @@ main(int argc, char* argv[]) {
         } else {
             LOG_DEBUG(dhcp6_logger, DBG_DHCP6_START, DHCP6_STANDALONE);
         }
-        if (!status) {
-            isc_throw(isc::Unexpected, "Failed to initialize configuration backend.");
-        }
 
         server.run();
         LOG_INFO(dhcp6_logger, DHCP6_SHUTDOWN);
diff --git a/src/bin/dhcp6/tests/Makefile.am b/src/bin/dhcp6/tests/Makefile.am
index f09eb3c18b2e84f941c8dfe1e624614aef4a4e66..1c8b6e5a69b32b11ccbe792570ca6fcbc31a3018 100644
--- a/src/bin/dhcp6/tests/Makefile.am
+++ b/src/bin/dhcp6/tests/Makefile.am
@@ -96,8 +96,8 @@ dhcp6_unittests_SOURCES += bundy_controller_unittest.cc
 endif
 
 if CONFIG_BACKEND_JSON
-dhcp6_unittests_SOURCES += ../jsonfile_controller.cc
-dhcp6_unittests_SOURCES += jsonfile_controller_unittest.cc
+dhcp6_unittests_SOURCES += ../kea_controller.cc
+dhcp6_unittests_SOURCES += kea_controller_unittest.cc
 endif
 
 nodist_dhcp6_unittests_SOURCES  = ../dhcp6_messages.h ../dhcp6_messages.cc
diff --git a/src/bin/dhcp6/tests/kea_controller_unittest.cc b/src/bin/dhcp6/tests/kea_controller_unittest.cc
index 1f70c042e1ea784114a9c15a5b74c6bdf98350a4..3198561345742e7e54981fd2dd394203f74ebc88 100644
--- a/src/bin/dhcp6/tests/kea_controller_unittest.cc
+++ b/src/bin/dhcp6/tests/kea_controller_unittest.cc
@@ -101,7 +101,7 @@ TEST_F(JSONFileBackendTest, jsonFile) {
     );
 
     // And configure it using the config file.
-    EXPECT_TRUE(srv->init(TEST_FILE));
+    EXPECT_NO_THROW(srv->init(TEST_FILE));
 
     // Now check if the configuration has been applied correctly.
     const Subnet6Collection* subnets = CfgMgr::instance().getSubnets6();
@@ -171,7 +171,7 @@ TEST_F(JSONFileBackendTest, comments) {
     );
 
     // And configure it using config without
-    EXPECT_TRUE(srv->init(TEST_FILE));
+    EXPECT_NO_THROW(srv->init(TEST_FILE));
 
     // Now check if the configuration has been applied correctly.
     const Subnet6Collection* subnets = CfgMgr::instance().getSubnets6();
@@ -190,4 +190,49 @@ TEST_F(JSONFileBackendTest, comments) {
     EXPECT_EQ(Lease::TYPE_NA, pools1.at(0)->getType());
 }
 
+// This test checks if configuration detects failure when trying:
+// - empty file
+// - empty filename
+// - no Dhcp6 element
+// - Config file that contains Dhcp6 but has a content error
+TEST_F(JSONFileBackendTest, configBroken) {
+
+    // Empty config is not allowed, because Dhcp6 element is missing
+    string config_empty = "";
+
+    // This config does not have mandatory Dhcp6 element
+    string config_v4 = "{ \"Dhcp4\": { \"interfaces\": [ \"*\" ],"
+        "\"preferred-lifetime\": 3000,"
+        "\"rebind-timer\": 2000, "
+        "\"renew-timer\": 1000, "
+        "\"subnet4\": [ { "
+        "    \"pool\": [ \"192.0.2.0/24\" ],"
+        "    \"subnet\": \"192.0.2.0/24\" "
+        " } ]}";
+
+    // This has Dhcp6 element, but it's utter nonsense
+    string config_nonsense = "{ \"Dhcp6\": { \"reviews\": \"are so much fun\" } }";
+
+    // Now initialize the server
+    boost::scoped_ptr<ControlledDhcpv6Srv> srv;
+    ASSERT_NO_THROW(
+        srv.reset(new ControlledDhcpv6Srv(0))
+    );
+
+    // Try to configure without filename. Should fail.
+    EXPECT_THROW(srv->init(""), BadValue);
+
+    // Try to configure it using empty file. Should fail.
+    writeFile(TEST_FILE, config_empty);
+    EXPECT_THROW(srv->init(TEST_FILE), BadValue);
+
+    // Now try to load a config that does not have Dhcp6 component.
+    writeFile(TEST_FILE, config_v4);
+    EXPECT_THROW(srv->init(TEST_FILE), BadValue);
+
+    // Now try to load a config with Dhcp6 full of nonsense.
+    writeFile(TEST_FILE, config_nonsense);
+    EXPECT_THROW(srv->init(TEST_FILE), BadValue);
+}
+
 } // End of anonymous namespace
diff --git a/src/lib/dhcpsrv/daemon.cc b/src/lib/dhcpsrv/daemon.cc
index c4ccfb86e8559c08f29de5018dfab2a27652a1ff..bb9566745e3d8f7bdd6d82d0abed346917629133 100644
--- a/src/lib/dhcpsrv/daemon.cc
+++ b/src/lib/dhcpsrv/daemon.cc
@@ -27,7 +27,7 @@ namespace dhcp {
 Daemon::Daemon() {
 }
 
-bool Daemon::init(const std::string&) {
+void Daemon::init(const std::string&) {
     return false;
 }
 
diff --git a/src/lib/dhcpsrv/daemon.h b/src/lib/dhcpsrv/daemon.h
index fe17938ca576c30fc7f494169a22ef7e5798fd5f..7c144890447242fc3b782e715446474fd77ee354 100644
--- a/src/lib/dhcpsrv/daemon.h
+++ b/src/lib/dhcpsrv/daemon.h
@@ -61,8 +61,8 @@ public:
     /// likely that the D2 will be started, it will analyze its config file,
     /// decide that it is not needed and will shut down.
     ///
-    /// @return true if initialization was successful, false if it was not
-    virtual bool init(const std::string& config_file);
+    /// @note this method may throw
+    virtual void init(const std::string& config_file);
 
     /// @brief Performs final deconfiguration.
     ///