diff --git a/ldpd/lde.c b/ldpd/lde.c
index 91b2b1727f..a28862881d 100644
--- a/ldpd/lde.c
+++ b/ldpd/lde.c
@@ -58,7 +58,7 @@ struct ldpd_conf	*ldeconf;
 struct nbr_tree		 lde_nbrs = RB_INITIALIZER(&lde_nbrs);
 
 static struct imsgev	*iev_ldpe;
-static struct imsgev	*iev_main;
+static struct imsgev	*iev_main, *iev_main_sync;
 
 /* Master of threads. */
 struct thread_master *master;
@@ -133,15 +133,18 @@ lde(const char *user, const char *group)
 	/* setup signal handler */
 	signal_init(master, array_size(lde_signals), lde_signals);
 
-	/* setup pipe and event handler to the parent process */
-	if ((iev_main = malloc(sizeof(struct imsgev))) == NULL)
+	/* setup pipes and event handlers to the parent process */
+	if ((iev_main = calloc(1, sizeof(struct imsgev))) == NULL)
 		fatal(NULL);
-	imsg_init(&iev_main->ibuf, 3);
+	imsg_init(&iev_main->ibuf, LDPD_FD_ASYNC);
 	iev_main->handler_read = lde_dispatch_parent;
 	iev_main->ev_read = thread_add_read(master, iev_main->handler_read,
 	    iev_main, iev_main->ibuf.fd);
 	iev_main->handler_write = ldp_write_handler;
-	iev_main->ev_write = NULL;
+
+	if ((iev_main_sync = calloc(1, sizeof(struct imsgev))) == NULL)
+		fatal(NULL);
+	imsg_init(&iev_main_sync->ibuf, LDPD_FD_SYNC);
 
 	/* start the LIB garbage collector */
 	lde_gc_start_timer();
@@ -162,6 +165,8 @@ lde_shutdown(void)
 	close(iev_ldpe->ibuf.fd);
 	msgbuf_clear(&iev_main->ibuf.w);
 	close(iev_main->ibuf.fd);
+	msgbuf_clear(&iev_main_sync->ibuf.w);
+	close(iev_main_sync->ibuf.fd);
 
 	lde_gc_stop_timer();
 	lde_nbr_clear();
@@ -171,6 +176,7 @@ lde_shutdown(void)
 
 	free(iev_ldpe);
 	free(iev_main);
+	free(iev_main_sync);
 
 	log_info("label decision engine exiting");
 	exit(0);
diff --git a/ldpd/ldpd.c b/ldpd/ldpd.c
index c9f4e37eee..6fd4251edc 100644
--- a/ldpd/ldpd.c
+++ b/ldpd/ldpd.c
@@ -42,7 +42,7 @@
 #include "qobj.h"
 
 static void		 ldpd_shutdown(void);
-static pid_t		 start_child(enum ldpd_process, char *, int,
+static pid_t		 start_child(enum ldpd_process, char *, int, int,
 			    const char *, const char *);
 static int		 main_dispatch_ldpe(struct thread *);
 static int		 main_dispatch_lde(struct thread *);
@@ -77,8 +77,8 @@ DEFINE_QOBJ_TYPE(ldpd_conf)
 struct ldpd_global	 global;
 struct ldpd_conf	*ldpd_conf;
 
-static struct imsgev	*iev_ldpe;
-static struct imsgev	*iev_lde;
+static struct imsgev	*iev_ldpe, *iev_ldpe_sync;
+static struct imsgev	*iev_lde, *iev_lde_sync;
 static pid_t		 ldpe_pid;
 static pid_t		 lde_pid;
 
@@ -207,8 +207,8 @@ main(int argc, char *argv[])
 {
 	char			*saved_argv0;
 	int			 lflag = 0, eflag = 0;
-	int			 pipe_parent2ldpe[2];
-	int			 pipe_parent2lde[2];
+	int			 pipe_parent2ldpe[2], pipe_parent2ldpe_sync[2];
+	int			 pipe_parent2lde[2], pipe_parent2lde_sync[2];
 	char			*p;
 	char			*vty_addr = NULL;
 	int			 vty_port = LDP_VTY_PORT;
@@ -347,22 +347,34 @@ main(int argc, char *argv[])
 
 	if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, pipe_parent2ldpe) == -1)
 		fatal("socketpair");
+	if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC,
+	    pipe_parent2ldpe_sync) == -1)
+		fatal("socketpair");
 	if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, pipe_parent2lde) == -1)
 		fatal("socketpair");
+	if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC,
+	    pipe_parent2lde_sync) == -1)
+		fatal("socketpair");
 	sock_set_nonblock(pipe_parent2ldpe[0]);
 	sock_set_cloexec(pipe_parent2ldpe[0]);
 	sock_set_nonblock(pipe_parent2ldpe[1]);
 	sock_set_cloexec(pipe_parent2ldpe[1]);
+	sock_set_nonblock(pipe_parent2ldpe_sync[0]);
+	sock_set_cloexec(pipe_parent2ldpe_sync[0]);
+	sock_set_cloexec(pipe_parent2ldpe_sync[1]);
 	sock_set_nonblock(pipe_parent2lde[0]);
 	sock_set_cloexec(pipe_parent2lde[0]);
 	sock_set_nonblock(pipe_parent2lde[1]);
 	sock_set_cloexec(pipe_parent2lde[1]);
+	sock_set_nonblock(pipe_parent2lde_sync[0]);
+	sock_set_cloexec(pipe_parent2lde_sync[0]);
+	sock_set_cloexec(pipe_parent2lde_sync[1]);
 
 	/* start children */
 	lde_pid = start_child(PROC_LDE_ENGINE, saved_argv0,
-	    pipe_parent2lde[1], user, group);
+	    pipe_parent2lde[1], pipe_parent2lde_sync[1], user, group);
 	ldpe_pid = start_child(PROC_LDP_ENGINE, saved_argv0,
-	    pipe_parent2ldpe[1], user, group);
+	    pipe_parent2ldpe[1], pipe_parent2ldpe_sync[1], user, group);
 
 	/* drop privileges */
 	if (user)
@@ -378,22 +390,34 @@ main(int argc, char *argv[])
 	ldp_zebra_init(master);
 
 	/* setup pipes to children */
-	if ((iev_ldpe = malloc(sizeof(struct imsgev))) == NULL ||
-	    (iev_lde = malloc(sizeof(struct imsgev))) == NULL)
+	if ((iev_ldpe = calloc(1, sizeof(struct imsgev))) == NULL ||
+	    (iev_ldpe_sync = calloc(1, sizeof(struct imsgev))) == NULL ||
+	    (iev_lde = calloc(1, sizeof(struct imsgev))) == NULL ||
+	    (iev_lde_sync = calloc(1, sizeof(struct imsgev))) == NULL)
 		fatal(NULL);
 	imsg_init(&iev_ldpe->ibuf, pipe_parent2ldpe[0]);
 	iev_ldpe->handler_read = main_dispatch_ldpe;
 	iev_ldpe->ev_read = thread_add_read(master, iev_ldpe->handler_read,
 	    iev_ldpe, iev_ldpe->ibuf.fd);
 	iev_ldpe->handler_write = ldp_write_handler;
-	iev_ldpe->ev_write = NULL;
+
+	imsg_init(&iev_ldpe_sync->ibuf, pipe_parent2ldpe_sync[0]);
+	iev_ldpe_sync->handler_read = main_dispatch_ldpe;
+	iev_ldpe_sync->ev_read = thread_add_read(master,
+	    iev_ldpe_sync->handler_read, iev_ldpe_sync, iev_ldpe_sync->ibuf.fd);
+	iev_ldpe_sync->handler_write = ldp_write_handler;
 
 	imsg_init(&iev_lde->ibuf, pipe_parent2lde[0]);
 	iev_lde->handler_read = main_dispatch_lde;
 	iev_lde->ev_read = thread_add_read(master, iev_lde->handler_read,
 	    iev_lde, iev_lde->ibuf.fd);
 	iev_lde->handler_write = ldp_write_handler;
-	iev_lde->ev_write = NULL;
+
+	imsg_init(&iev_lde_sync->ibuf, pipe_parent2lde_sync[0]);
+	iev_lde_sync->handler_read = main_dispatch_lde;
+	iev_lde_sync->ev_read = thread_add_read(master,
+	    iev_lde_sync->handler_read, iev_lde_sync, iev_lde_sync->ibuf.fd);
+	iev_lde_sync->handler_write = ldp_write_handler;
 
 	if (main_imsg_send_ipc_sockets(&iev_ldpe->ibuf, &iev_lde->ibuf))
 		fatal("could not establish imsg links");
@@ -466,8 +490,8 @@ ldpd_shutdown(void)
 }
 
 static pid_t
-start_child(enum ldpd_process p, char *argv0, int fd, const char *user,
-    const char *group)
+start_child(enum ldpd_process p, char *argv0, int fd_async, int fd_sync,
+    const char *user, const char *group)
 {
 	char	*argv[7];
 	int	 argc = 0;
@@ -479,12 +503,15 @@ start_child(enum ldpd_process p, char *argv0, int fd, const char *user,
 	case 0:
 		break;
 	default:
-		close(fd);
+		close(fd_async);
+		close(fd_sync);
 		return (pid);
 	}
 
-	if (dup2(fd, 3) == -1)
-		fatal("cannot setup imsg fd");
+	if (dup2(fd_async, LDPD_FD_ASYNC) == -1)
+		fatal("cannot setup imsg async fd");
+	if (dup2(fd_sync, LDPD_FD_SYNC) == -1)
+		fatal("cannot setup imsg sync fd");
 
 	argv[argc++] = argv0;
 	switch (p) {
@@ -702,10 +729,11 @@ main_imsg_compose_both(enum imsg_type type, void *buf, uint16_t len)
 void
 imsg_event_add(struct imsgev *iev)
 {
-	THREAD_READ_ON(master, iev->ev_read, iev->handler_read, iev,
-	    iev->ibuf.fd);
+	if (iev->handler_read)
+		THREAD_READ_ON(master, iev->ev_read, iev->handler_read, iev,
+		    iev->ibuf.fd);
 
-	if (iev->ibuf.w.queued)
+	if (iev->handler_write && iev->ibuf.w.queued)
 		THREAD_WRITE_ON(master, iev->ev_write, iev->handler_write, iev,
 		    iev->ibuf.fd);
 }
diff --git a/ldpd/ldpd.h b/ldpd/ldpd.h
index 3f6d7ac569..2c9706cf47 100644
--- a/ldpd/ldpd.h
+++ b/ldpd/ldpd.h
@@ -33,6 +33,9 @@
 #define CONF_FILE		"/etc/ldpd.conf"
 #define LDPD_USER		"_ldpd"
 
+#define LDPD_FD_ASYNC		3
+#define LDPD_FD_SYNC		4
+
 #define LDPD_OPT_VERBOSE	0x00000001
 #define LDPD_OPT_VERBOSE2	0x00000002
 #define LDPD_OPT_NOACTION	0x00000004
diff --git a/ldpd/ldpe.c b/ldpd/ldpe.c
index 1a60af8f41..236e71f322 100644
--- a/ldpd/ldpe.c
+++ b/ldpd/ldpe.c
@@ -48,7 +48,7 @@ struct ldpd_conf	*leconf;
 struct ldpd_sysdep	 sysdep;
 #endif
 
-static struct imsgev	*iev_main;
+static struct imsgev	*iev_main, *iev_main_sync;
 static struct imsgev	*iev_lde;
 #ifdef __OpenBSD__
 static struct thread	*pfkey_ev;
@@ -142,15 +142,18 @@ ldpe(const char *user, const char *group)
 	/* setup signal handler */
 	signal_init(master, array_size(ldpe_signals), ldpe_signals);
 
-	/* setup pipe and event handler to the parent process */
-	if ((iev_main = malloc(sizeof(struct imsgev))) == NULL)
+	/* setup pipes and event handlers to the parent process */
+	if ((iev_main = calloc(1, sizeof(struct imsgev))) == NULL)
 		fatal(NULL);
-	imsg_init(&iev_main->ibuf, 3);
+	imsg_init(&iev_main->ibuf, LDPD_FD_ASYNC);
 	iev_main->handler_read = ldpe_dispatch_main;
 	iev_main->ev_read = thread_add_read(master, iev_main->handler_read,
 	    iev_main, iev_main->ibuf.fd);
 	iev_main->handler_write = ldp_write_handler;
-	iev_main->ev_write = NULL;
+
+	if ((iev_main_sync = calloc(1, sizeof(struct imsgev))) == NULL)
+		fatal(NULL);
+	imsg_init(&iev_main_sync->ibuf, LDPD_FD_SYNC);
 
 #ifdef __OpenBSD__
 	if (sysdep.no_pfkey == 0)
@@ -191,6 +194,8 @@ ldpe_shutdown(void)
 	msgbuf_write(&iev_main->ibuf.w);
 	msgbuf_clear(&iev_main->ibuf.w);
 	close(iev_main->ibuf.fd);
+	msgbuf_clear(&iev_main_sync->ibuf.w);
+	close(iev_main_sync->ibuf.fd);
 
 	control_cleanup();
 	config_clear(leconf);
@@ -215,6 +220,7 @@ ldpe_shutdown(void)
 	/* clean up */
 	free(iev_lde);
 	free(iev_main);
+	free(iev_main_sync);
 	free(pkt_ptr);
 
 	log_info("ldp engine exiting");