+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.