diff --git a/include/stp_externs.h b/include/stp_externs.h
index 87ed966..db525c2 100755
--- a/include/stp_externs.h
+++ b/include/stp_externs.h
@@ -105,6 +105,7 @@ extern bool stpmgr_config_root_protect(PORT_ID port_id, bool enable);
 /* stp_util.c */
 extern bool stputil_is_protocol_enabled(L2_PROTO_MODE proto_mode);
 extern bool stputil_is_port_untag(VLAN_ID vlan_id, PORT_ID port_id);
+extern VLAN_ID stputil_get_untag_vlan(PORT_ID port_id);
 extern void stputil_bridge_to_string(BRIDGE_IDENTIFIER *bridge_id, UINT8 *buffer, UINT16 size);
 extern UINT32 stputil_get_default_path_cost(PORT_ID port_number, bool extend);
 extern UINT32 stputil_get_path_cost(STP_PORT_SPEED port_speed, bool extend);
diff --git a/include/stp_ipc.h b/include/stp_ipc.h
index 6585329..e663680 100644
--- a/include/stp_ipc.h
+++ b/include/stp_ipc.h
@@ -74,7 +74,7 @@ typedef struct STP_IPC_MSG
     unsigned int msg_len;
     L2_PROTO_MODE proto_mode;
     char data[0];
-} __attribute__((aligned(4))) STP_IPC_MSG;
+} __attribute__((packed)) STP_IPC_MSG;
 
 #define STP_SET_COMMAND 1
 #define STP_DEL_COMMAND 0
@@ -98,7 +98,9 @@ typedef struct PORT_ATTR
     char intf_name[IFNAMSIZ];
     int8_t mode;
     uint8_t enabled;
-} PORT_ATTR;
+    // Add padding to align to 4 bytes
+    uint16_t padding;
+} __attribute__((packed)) PORT_ATTR;
 
 typedef struct STP_VLAN_CONFIG_MSG
 {
@@ -126,11 +128,11 @@ typedef struct STP_VLAN_PORT_CONFIG_MSG
 
 typedef struct VLAN_ATTR
 {
-    int8_t mode;
-    uint8_t padding[3];  // Explicit padding for alignment
     int inst_id;
     int vlan_id;
-} VLAN_ATTR;
+    int8_t mode;
+    uint8_t padding[3];  // Explicit padding for alignment
+} __attribute__((packed)) VLAN_ATTR;
 
 typedef struct STP_PORT_CONFIG_MSG
 {
@@ -138,17 +140,18 @@ typedef struct STP_PORT_CONFIG_MSG
     char intf_name[IFNAMSIZ];
     uint8_t enabled;
     uint8_t root_guard;
+    uint8_t loop_guard;
     uint8_t bpdu_guard;
     uint8_t bpdu_guard_do_disable;
     uint8_t portfast;
     uint8_t uplink_fast;
-    uint8_t edge;
+    uint8_t edge_port;
     LinkType    link_type;          // MSTP only
     int path_cost;
     int priority;
     int count;
     VLAN_ATTR vlan_list[0];
-} STP_PORT_CONFIG_MSG;
+} __attribute__((packed)) STP_PORT_CONFIG_MSG;
 
 typedef struct STP_VLAN_MEM_CONFIG_MSG
 {
@@ -161,7 +164,7 @@ typedef struct STP_VLAN_MEM_CONFIG_MSG
     char intf_name[IFNAMSIZ];
     int path_cost;
     int priority;
-} STP_VLAN_MEM_CONFIG_MSG;
+} __attribute__((packed)) STP_VLAN_MEM_CONFIG_MSG;
 
 typedef struct STP_MST_GLOBAL_CONFIG_MSG {
     uint8_t     opcode; // enable/disable
@@ -170,26 +173,26 @@ typedef struct STP_MST_GLOBAL_CONFIG_MSG {
     uint8_t     forward_delay;
     uint8_t     hello_time;
     uint8_t     max_age;
-    uint8_t     max_hop;
+    uint8_t     max_hops;
 }__attribute__((packed)) STP_MST_GLOBAL_CONFIG_MSG;
 
 
 typedef struct VLAN_LIST{
     uint16_t    vlan_id;
-}VLAN_LIST;
+}__attribute__((packed)) VLAN_LIST;
 
-typedef struct MST_INST_CONFIG_MSG
+typedef struct STP_MST_INST_CONFIG_MSG
 {
     uint8_t     opcode; // enable/disable
     uint16_t    mst_id;
     int         priority;
     uint16_t    vlan_count;
     VLAN_LIST   vlan_list[0];
-} __attribute__((packed))  MST_INST_CONFIG_MSG;
+} __attribute__((packed))  STP_MST_INST_CONFIG_MSG;
 
 typedef struct STP_MST_INSTANCE_CONFIG_MSG {
     uint8_t    mst_count;
-    MST_INST_CONFIG_MSG mst_list[0];
+    STP_MST_INST_CONFIG_MSG  mst_list[0];
 } __attribute__((packed)) STP_MST_INSTANCE_CONFIG_MSG;
 
 typedef struct STP_MST_INST_PORT_CONFIG_MSG {
@@ -204,7 +207,7 @@ typedef struct PORT_LIST
 {
     char        intf_name[IFNAMSIZ];
     int8_t      tagging_mode;
-}PORT_LIST;
+}__attribute__((packed)) PORT_LIST;
 
 typedef struct STP_MST_VLAN_PORT_MAP
 {
@@ -213,7 +216,7 @@ typedef struct STP_MST_VLAN_PORT_MAP
     int8_t      stp_mode;
     uint8_t     add;    
     PORT_LIST   port_list[0];
-}STP_MST_VLAN_PORT_MAP;
+}__attribute__((packed)) STP_MST_VLAN_PORT_MAP;
 
 typedef struct MSTP_INST_VLAN_LIST
 {
diff --git a/mstp/mstp_mgr.c b/mstp/mstp_mgr.c
index fa78f5d..b914518 100755
--- a/mstp/mstp_mgr.c
+++ b/mstp/mstp_mgr.c
@@ -2211,7 +2211,7 @@ void mstpmgr_process_intf_config_msg(void *msg)
             "do_dis:%d, cost:%d, pri:%d, edge:%d, count:%d",
             pmsg->intf_name, pmsg->opcode, pmsg->enabled, pmsg->root_guard, pmsg->bpdu_guard,
             pmsg->bpdu_guard_do_disable, pmsg->path_cost, pmsg->priority,
-            pmsg->edge, pmsg->count);
+            pmsg->edge_port, pmsg->count);
 
 
     port_id = stp_intf_get_port_id_by_name(pmsg->intf_name);
@@ -2286,7 +2286,7 @@ void mstpmgr_process_intf_config_msg(void *msg)
         {
             mstpmgr_add_control_port(port_id);
 
-            mstpmgr_config_port_admin_edge(port_id, pmsg->edge);
+            mstpmgr_config_port_admin_edge(port_id, pmsg->edge_port);
 
             mstpmgr_config_root_protect(port_id, pmsg->root_guard);
 
@@ -2520,8 +2520,8 @@ void mstpmgr_process_mstp_global_config_msg(void *msg)
         else
             mstpmgr_config_max_age(MSTP_DFLT_MAX_AGE);  
 
-        if(pmsg->max_hop)
-            mstpmgr_config_max_hops(pmsg->max_hop);
+        if(pmsg->max_hops)
+            mstpmgr_config_max_hops(pmsg->max_hops);
         else
             mstpmgr_config_max_hops(MSTP_DFLT_MAX_HOPS);
     }
@@ -2545,7 +2545,7 @@ void mstpmgr_process_mstp_global_config_msg(void *msg)
         if(!pmsg->max_age)
             mstpmgr_config_max_age(MSTP_DFLT_MAX_AGE);
 
-        if(!pmsg->max_hop)
+        if(!pmsg->max_hops)
             mstpmgr_config_max_hops(MSTP_DFLT_MAX_HOPS);
 
     }
@@ -2566,7 +2566,7 @@ void mstpmgr_process_inst_vlan_config_msg(void *msg)
     PORT_MASK *mem_port_mask;
     PORT_MASK  *cist_port_mask = portmask_local_init(&cist_mask);
     PORT_MASK  *msti_port_mask = portmask_local_init(&msti_mask);
-    MST_INST_CONFIG_MSG *mst_list;
+    STP_MST_INST_CONFIG_MSG *mst_list;
     MSTP_MSTID  mst_id;
     VLAN_ID   vlan_id = VLAN_ID_INVALID;
     UINT8 vlanmask_string[500] = {0,};
@@ -2598,7 +2598,7 @@ void mstpmgr_process_inst_vlan_config_msg(void *msg)
         {
             mstpmgr_config_cist_priority(mst_list->priority);
 
-            mst_list = (MST_INST_CONFIG_MSG *)((char *)mst_list  + (sizeof(MST_INST_CONFIG_MSG)));
+            mst_list = (STP_MST_INST_CONFIG_MSG *)((char *)mst_list  + (sizeof(STP_MST_INST_CONFIG_MSG)));
             continue;
         }
         else
@@ -2607,7 +2607,7 @@ void mstpmgr_process_inst_vlan_config_msg(void *msg)
              * Ignore it, will update priority once the instance to vlan mapping comes */
             if(mst_list->opcode == STP_SET_COMMAND && mst_list->vlan_count == 0)
             {
-                mst_list = (MST_INST_CONFIG_MSG *)((char *)mst_list  + (sizeof(MST_INST_CONFIG_MSG)));
+                mst_list = (STP_MST_INST_CONFIG_MSG *)((char *)mst_list  + (sizeof(STP_MST_INST_CONFIG_MSG)));
                 continue;
             }
         }
@@ -2813,7 +2813,7 @@ void mstpmgr_process_inst_vlan_config_msg(void *msg)
             }
         }
 
-        mst_list = (MST_INST_CONFIG_MSG *)((char *)mst_list  + (sizeof(MST_INST_CONFIG_MSG)) + (mst_list->vlan_count * sizeof(VLAN_LIST)));
+        mst_list = (STP_MST_INST_CONFIG_MSG *)((char *)mst_list  + (sizeof(STP_MST_INST_CONFIG_MSG)) + (mst_list->vlan_count * sizeof(VLAN_LIST)));
     }
    
     if(restart)
diff --git a/stp/stp_intf.c b/stp/stp_intf.c
index cd016bb..b0cc090 100755
--- a/stp/stp_intf.c
+++ b/stp/stp_intf.c
@@ -485,12 +485,20 @@ void stp_intf_netlink_cb(netlink_db_t *if_db, uint8_t is_add, bool init_in_prog)
     bool eth_if;
     g_stpd_stats_libev_netlink++;
 
-    if(STP_IS_ETH_PORT(if_db->ifname))
-        eth_if = true;
-    else if(STP_IS_PO_PORT(if_db->ifname))
-        eth_if = false;
-    else
-        return;
+    if ( STP_IS_ETH_PORT( if_db->ifname ) ) {
+         eth_if = true;
+    } else if ( STP_IS_PO_PORT( if_db->ifname ) ) {
+         eth_if = false;
+    } else {
+        // If it is delete then if_db->ifname can be NULL since the
+        // delete path relies on if_db->kif_index. For add we need to
+        // have if_db->ifname
+        if ( is_add ) {
+            STP_LOG_ERR( "Interface '%s' neither port nor portchannel",
+                         if_db->ifname );
+           return;
+        }
+    }
 
     node = stp_intf_update_intf_db(if_db, is_add, init_in_prog, eth_if);
 
diff --git a/stp/stp_main.c b/stp/stp_main.c
index 497b240..cd5921e 100644
--- a/stp/stp_main.c
+++ b/stp/stp_main.c
@@ -27,7 +27,7 @@ int stpd_ipc_init()
 
     unlink(STPD_SOCK_NAME);
     g_stpd_ipc_handle = socket(AF_UNIX, SOCK_DGRAM, 0);
-    if (!g_stpd_ipc_handle)
+    if (g_stpd_ipc_handle == -1 )
     {
         STP_LOG_ERR("ipc socket error %s", strerror(errno));
         return -1;
@@ -62,6 +62,7 @@ int stpd_ipc_init()
 void stpd_log_init()
 {
     STP_LOG_INIT();
+
     if (fopen("/stpd_dbg_reload", "r"))
     {
         STP_LOG_SET_LEVEL(STP_LOG_LEVEL_DEBUG);
@@ -78,7 +79,6 @@ int stpd_main()
     struct event   *evtimer_100ms = 0;
     struct event   *evpkt = 0;
     struct event_config *cfg = 0;
-    int8_t ret = 0;
 
     signal(SIGPIPE, SIG_IGN);
 
diff --git a/stp/stp_mgr.c b/stp/stp_mgr.c
index 1cfcc6b..172205a 100755
--- a/stp/stp_mgr.c
+++ b/stp/stp_mgr.c
@@ -1505,6 +1505,12 @@ void stpmgr_rx_pvst_bpdu(uint16_t vlan_id, uint32_t port_id, void *pkt)
 
 void stpmgr_process_rx_bpdu(uint16_t vlan_id, uint32_t port_id, unsigned char *pkt)
 {
+    // When BPDUs arrive without VLAN get the VLAN from port's untagged vlan
+    // configuration.
+    if ( vlan_id == 0 ) {
+        vlan_id = stputil_get_untag_vlan(port_id);
+    }
+
     // sanity checks
     if (!IS_VALID_VLAN(vlan_id))
     {
@@ -1866,7 +1872,8 @@ static void stpmgr_process_vlan_mem_config_msg(void *msg)
 static void stpmgr_process_ipc_msg(STP_IPC_MSG *msg, int len, struct sockaddr_un client_addr)
 {
     int ret;
-    STP_LOG_INFO("rcvd %s msg type", msgtype_str[msg->msg_type]);
+
+    STP_LOG_INFO("rcvd %s msg type proto_mode %d", msgtype_str[msg->msg_type], msg->proto_mode);
 
     /* Temp code until warm boot is handled */
     if(msg->msg_type != STP_INIT_READY && msg->msg_type != STP_STPCTL_MSG)
@@ -1906,6 +1913,9 @@ static void stpmgr_process_ipc_msg(STP_IPC_MSG *msg, int len, struct sockaddr_un
             else if(msg->proto_mode == L2_MSTP)
             {
                 mstpmgr_process_bridge_config_msg(msg->data);
+            } else
+            {
+                STP_LOG_ERR("Invalid proto_mode %d", msg->proto_mode);
             }
             break;
         }
@@ -1914,6 +1924,9 @@ static void stpmgr_process_ipc_msg(STP_IPC_MSG *msg, int len, struct sockaddr_un
             if(msg->proto_mode == L2_PVSTP)
             {
                 stpmgr_process_vlan_config_msg(msg->data);
+            } else
+            {
+                STP_LOG_ERR("Invalid proto_mode %d", msg->proto_mode);
             }
             break;
         }
@@ -1922,6 +1935,9 @@ static void stpmgr_process_ipc_msg(STP_IPC_MSG *msg, int len, struct sockaddr_un
             if(msg->proto_mode == L2_PVSTP)
             {
                 stpmgr_process_vlan_intf_config_msg(msg->data);
+            } else
+            {
+                STP_LOG_ERR("Invalid proto_mode %d", msg->proto_mode);
             }
             break;
         }
@@ -1934,6 +1950,9 @@ static void stpmgr_process_ipc_msg(STP_IPC_MSG *msg, int len, struct sockaddr_un
             else if(msg->proto_mode == L2_MSTP)
             {
                 mstpmgr_process_intf_config_msg(msg->data);
+            } else
+            {
+                STP_LOG_ERR("Invalid proto_mode %d", msg->proto_mode);
             }
             break;
         }
@@ -1942,6 +1961,9 @@ static void stpmgr_process_ipc_msg(STP_IPC_MSG *msg, int len, struct sockaddr_un
             if(msg->proto_mode == L2_PVSTP)
             {
                 stpmgr_process_vlan_mem_config_msg(msg->data);
+            } else
+            {
+                STP_LOG_ERR("Invalid proto_mode %d", msg->proto_mode);
             }
             break;
         }
@@ -1955,6 +1977,9 @@ static void stpmgr_process_ipc_msg(STP_IPC_MSG *msg, int len, struct sockaddr_un
             else if (STP_IS_PROTOCOL_ENABLED(L2_MSTP))
             {
                 mstpdbg_process_ctl_msg(msg->data);
+            } else
+            {
+                STP_LOG_ERR("Invalid proto_mode %d", msg->proto_mode);
             }
             stpmgr_send_reply(client_addr, (void *)msg, len);
             break;
diff --git a/stp/stp_netlink.c b/stp/stp_netlink.c
index 51dde3a..0cbbb22 100644
--- a/stp/stp_netlink.c
+++ b/stp/stp_netlink.c
@@ -290,8 +290,7 @@ static int stp_netlink_recv(int nl_fd, bool read_all)
                 nh_len = nh->nlmsg_len;
 
                 stp_netlink_parse_rtattr(rt_list, IFLA_MAX, IFLA_RTA(ifi), nh_len);
-                if (rt_list[IFLA_IFNAME])
-                {
+                if ( rt_list[IFLA_IFNAME] ) {
                     ptr = rt_list[IFLA_IFNAME];
                     strncpy(if_db.ifname, (char *)RTA_DATA(ptr), IFNAMSIZ - 1);
                     if_db.ifname[IFNAMSIZ - 1] = '\0';
@@ -355,15 +354,23 @@ static int stp_netlink_recv(int nl_fd, bool read_all)
                             if_db.master_ifindex = *(uint32_t *)RTA_DATA(ptr);
                         }
                     }
-                    STP_LOG_INFO("RTM-%s IF:%s KIF:%u Oper:%d Bond:%d Mem:%d Master:%u", (nh->nlmsg_type == RTM_NEWLINK)?"UPDATE":"DELETE", 
-                            if_db.ifname, if_db.kif_index, if_db.oper_state, if_db.is_bond, if_db.is_member, if_db.master_ifindex); 
-                }
-                else
-                {
-                    STP_LOG_DEBUG("No ifname for kif_index :%d ", if_db.kif_index);
+                    STP_LOG_DEBUG( "RTM-%s IF:%s KIF:%u Oper:%d Bond:%d Mem:%d Master:%u",
+                                   (nh->nlmsg_type == RTM_NEWLINK)?"UPDATE":"DELETE",
+                                   if_db.ifname, if_db.kif_index, if_db.oper_state,
+                                   if_db.is_bond, if_db.is_member, if_db.master_ifindex);
+
+                    stp_netlink_cb( &if_db,
+                                    ( ( nh->nlmsg_type == RTM_NEWLINK ) ? 1 : 0 ),
+                                    read_all );
+                } else {
+                    // RTM_DELLINK may omit IFLA_IFNAME; delete path uses kif_index only.
+                    if (nh->nlmsg_type == RTM_DELLINK) {
+                        stp_netlink_cb( &if_db, 0, read_all );
+                    } else {
+                        STP_LOG_DEBUG("No ifname for kif_index :%d ", if_db.kif_index);
+                    }
                 }
             }
-            stp_netlink_cb(&if_db, (nh->nlmsg_type == RTM_NEWLINK)?1:0, read_all);
         } //end for loop
 
 
diff --git a/stpctl/stpctl.c b/stpctl/stpctl.c
index 7381101..9f2d6d2 100644
--- a/stpctl/stpctl.c
+++ b/stpctl/stpctl.c
@@ -83,6 +83,8 @@ int connect_server()
         close(stpd_fd);
         return -1;
     }
+
+    return 0;
 }
 
 int send_msg_stpd(STP_MSG_TYPE msgType, uint32_t msgLen, void *data)