diff -up dhcp-4.3.4/configure.ac.sd_notify dhcp-4.3.4/configure.ac
--- dhcp-4.3.4/configure.ac.sd_notify	2016-04-29 13:08:52.813287060 +0200
+++ dhcp-4.3.4/configure.ac	2016-04-29 13:08:52.872287075 +0200
@@ -832,6 +832,17 @@ if test x$ldap = xyes || test x$ldapcryp
     AC_SUBST(LDAP_CFLAGS, [$LDAP_CFLAGS])
 fi
 
+AC_ARG_WITH(systemd,
+        AC_HELP_STRING([--with-systemd],
+                       [enable sending status notifications to systemd daemon (default is no)]),
+        [systemd=$withval],
+        [systemd=no])
+
+if test x$systemd = xyes ; then
+   AC_CHECK_LIB(systemd, sd_notifyf, ,
+                AC_MSG_FAILURE([*** systemd library not present - do you need to install systemd-libs package?]))
+fi
+
 # Append selected warning levels to CFLAGS before substitution (but after
 # AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[]], [[]])],[],[]) & etc).
 CFLAGS="$CFLAGS $STD_CWARNINGS"
diff -up dhcp-4.3.4/relay/dhcrelay.c.sd_notify dhcp-4.3.4/relay/dhcrelay.c
--- dhcp-4.3.4/relay/dhcrelay.c.sd_notify	2016-04-29 13:08:52.814287061 +0200
+++ dhcp-4.3.4/relay/dhcrelay.c	2016-04-29 13:08:52.872287075 +0200
@@ -37,6 +37,10 @@
    int keep_capabilities = 0;
 #endif
 
+#ifdef HAVE_LIBSYSTEMD
+#include <systemd/sd-daemon.h>
+#endif
+
 TIME default_lease_time = 43200; /* 12 hours... */
 TIME max_lease_time = 86400; /* 24 hours... */
 struct tree_cache *global_options[256];
@@ -709,6 +713,14 @@ main(int argc, char **argv) {
 	}
 #endif
 
+#ifdef HAVE_LIBSYSTEMD
+        /* We are ready to process incomming packets. Let's notify systemd */
+        sd_notifyf(0, "READY=1\n"
+                   "STATUS=Dispatching packets...\n"
+                   "MAINPID=%lu",
+                   (unsigned long) getpid());
+#endif
+
 	/* Start dispatching packets and timeouts... */
 	dispatch();
 
diff -up dhcp-4.3.4/server/dhcpd.c.sd_notify dhcp-4.3.4/server/dhcpd.c
--- dhcp-4.3.4/server/dhcpd.c.sd_notify	2016-04-29 13:08:52.873287075 +0200
+++ dhcp-4.3.4/server/dhcpd.c	2016-04-29 13:12:00.655333096 +0200
@@ -57,6 +57,10 @@ uid_t set_uid = 0;
 gid_t set_gid = 0;
 #endif /* PARANOIA */
 
+#ifdef HAVE_LIBSYSTEMD
+#include <systemd/sd-daemon.h>
+#endif
+
 struct iaddr server_identifier;
 int server_identifier_matched;
 
@@ -931,6 +935,14 @@ main(int argc, char **argv) {
 	/* Log that we are about to start working */
 	log_info("Server starting service.");
 
+#ifdef HAVE_LIBSYSTEMD
+        /* We are ready to process incomming packets. Let's notify systemd */
+        sd_notifyf(0, "READY=1\n"
+                   "STATUS=Dispatching packets...\n"
+                   "MAINPID=%lu",
+                   (unsigned long) getpid());
+#endif
+
 	/*
 	 * Receive packets and dispatch them...
 	 * dispatch() will never return.