diff -up ypserv-2.28/configure.in.sdnotify ypserv-2.28/configure.in
--- ypserv-2.28/configure.in.sdnotify	2012-07-12 14:29:03.491853939 +0200
+++ ypserv-2.28/configure.in	2012-07-12 14:29:03.505854057 +0200
@@ -269,6 +269,19 @@ if test "$ac_cv_func_getrpcport" = no; t
 	             [ac_cv_func_getrpcport=yes; LIBS="-lrpcsvc $LIBS"])
 fi
 
+USE_SD_NOTIFY=0
+AC_SUBST(USE_SD_NOTIFY)
+AC_CHECK_LIB(systemd-daemon,sd_notify,LIBSYSTEMD_DAEMON="-lsystemd-daemon",
+	LIBSYSTEMD_DAEMON="")
+if test -n "$LIBSYSTEMD_DAEMON" ; then
+	AC_CHECK_HEADERS(systemd/sd-daemon.h)
+	if test "$ac_cv_header_systemd_sd_notify_h" = yes; then
+          USE_SD_NOTIFY=1
+        fi
+fi
+AC_SUBST(USE_SD_NOTIFY)
+AC_SUBST(LIBSYSTEMD_DAEMON)
+
 AC_CHECK_LIB(nsl,gethostbyname)
 AC_CHECK_LIB(socket,socket)
 AC_CHECK_LIB(resolv, res_gethostbyname, RESOLV="-lresolv", RESOLV="")
@@ -357,7 +370,7 @@ Configuration:
   Compiler flags:         ${CFLAGS}
   Preprocessor:		  ${CPP}
   Preprocessor flags:     ${CPPFLAGS}
-  Libraries:		  ${LIBS} ${LIBDBM} ${LIBCRYPT}
+  Libraries:		  ${LIBS} ${LIBDBM} ${LIBCRYPT} ${LIBSYSTEMD_DAEMON}
   Awk:                    ${AWK}
   Shell:		  ${BASH}
   NIS map dir:            ${YPMAPDIR}
diff -up ypserv-2.28/lib/access.c.sdnotify ypserv-2.28/lib/access.c
--- ypserv-2.28/lib/access.c.sdnotify	2011-08-31 13:40:11.000000000 +0200
+++ ypserv-2.28/lib/access.c	2012-07-12 14:29:03.505854057 +0200
@@ -30,6 +30,9 @@
 #include <sys/socket.h>
 #include <netinet/in.h>
 #include <arpa/inet.h>
+#if defined(HAVE_SYSTEMD_SD_DAEMON_H)
+#include <systemd/sd-daemon.h>
+#endif
 
 #include "log_msg.h"
 #include "ypserv_conf.h"
@@ -215,3 +218,25 @@ is_valid (struct svc_req *rqstp, const c
 
   return status;
 }
+
+/* Send a messages to systemd daemon, that inicialization of daemon
+   is finished and daemon is ready to accept connections.
+   It is a nop if we don't use systemd. */
+void
+announce_ready()
+{
+#ifdef USE_SD_NOTIFY
+  int result;
+
+  result = sd_notifyf(0, "READY=1\n"
+                         "STATUS=Processing requests...\n"
+                         "MAINPID=%lu", (unsigned long) getpid());
+
+  /* Return code from sd_notifyf can be ignored, as per sd_notifyf(3).
+     However, if we use systemd's native unit file, we need to send 
+     this message to let systemd know that daemon is ready.
+     Thus, we want to know that the call had some issues. */
+  if (result < 0)
+    log_msg ("sd_notifyf failed: %s\n", strerror(-result));
+#endif
+}
diff -up ypserv-2.28/lib/Makefile.am.sdnotify ypserv-2.28/lib/Makefile.am
--- ypserv-2.28/lib/Makefile.am.sdnotify	2010-02-23 14:44:55.000000000 +0100
+++ ypserv-2.28/lib/Makefile.am	2012-07-12 14:29:03.506854065 +0200
@@ -13,7 +13,8 @@ noinst_HEADERS = log_msg.h yp.h ypserv_c
 
 rpcsvc_HEADERS = ypxfrd.x
 
-DEFS = @DEFS@ -D_REENTRANT=1 -DCONFDIR=\"$(sysconfdir)\" -DUSE_SLP=@USE_SLP@
+DEFS = @DEFS@ -D_REENTRANT=1 -DCONFDIR=\"$(sysconfdir)\" -DUSE_SLP=@USE_SLP@ \
+	-DUSE_SD_NOTIFY=@USE_SD_NOTIFY@
 INCLUDES = -I$(top_srcdir) -I$(top_builddir) -I$(srcdir)
 AM_CFLAGS = @PIE_CFLAGS@
 
diff -up ypserv-2.28/rpc.yppasswdd/Makefile.am.sdnotify ypserv-2.28/rpc.yppasswdd/Makefile.am
--- ypserv-2.28/rpc.yppasswdd/Makefile.am.sdnotify	2006-08-02 15:05:04.000000000 +0200
+++ ypserv-2.28/rpc.yppasswdd/Makefile.am	2012-07-12 14:29:03.506854065 +0200
@@ -24,7 +24,7 @@ sbin_PROGRAMS = rpc.yppasswdd
 
 rpc_yppasswdd_SOURCES = update.c yppasswd_xdr.c yppasswdd.c
 
-rpc_yppasswdd_LDADD =  @PIE_LDFLAGS@ $(LIBDBM) $(LIBCRYPT) $(top_builddir)/lib/libyp.a
+rpc_yppasswdd_LDADD =  @PIE_LDFLAGS@ $(LIBDBM) $(LIBCRYPT) $(LIBSYSTEMD_DAEMON) $(top_builddir)/lib/libyp.a
 rpc_yppasswdd_CFLAGS = @PIE_CFLAGS@
 
 if ENABLE_REGENERATE_MAN
diff -up ypserv-2.28/rpc.yppasswdd/yppasswdd.c.sdnotify ypserv-2.28/rpc.yppasswdd/yppasswdd.c
--- ypserv-2.28/rpc.yppasswdd/yppasswdd.c.sdnotify	2012-07-12 14:29:03.494853964 +0200
+++ ypserv-2.28/rpc.yppasswdd/yppasswdd.c	2012-07-12 14:29:03.507854073 +0200
@@ -457,6 +457,13 @@ main (int argc, char **argv)
       exit (1);
     }
 
+  /* If we use systemd as an init system, we may want to give it 
+     a message, that this daemon is ready to accept connections.
+     At this time, sockets for receiving connections are already 
+     created, so we can say we're ready now. It is a nop if we 
+     don't use systemd. */
+  announce_ready();
+
   /* Run the server */
   svc_run ();
   log_msg ("svc_run returned\n");
diff -up ypserv-2.28/rpc.ypxfrd/Makefile.am.sdnotify ypserv-2.28/rpc.ypxfrd/Makefile.am
--- ypserv-2.28/rpc.ypxfrd/Makefile.am.sdnotify	2012-07-12 14:29:42.795191749 +0200
+++ ypserv-2.28/rpc.ypxfrd/Makefile.am	2012-07-12 14:30:04.450388983 +0200
@@ -22,7 +22,7 @@ sbin_PROGRAMS = rpc.ypxfrd
 
 rpc_ypxfrd_SOURCES = ypxfrd.c ypxfrd_server.c ypxfrd_svc.c
 
-rpc_ypxfrd_LDADD = @PIE_LDFLAGS@ $(top_builddir)/lib/libyp.a @LIBDBM@
+rpc_ypxfrd_LDADD = @PIE_LDFLAGS@ $(top_builddir)/lib/libyp.a @LIBDBM@ $(LIBSYSTEMD_DAEMON)
 rpc_ypxfrd_CFLAGS = @PIE_CFLAGS@
 
 if ENABLE_REGENERATE_MAN
diff -up ypserv-2.28/rpc.ypxfrd/ypxfrd.c.sdnotify ypserv-2.28/rpc.ypxfrd/ypxfrd.c
--- ypserv-2.28/rpc.ypxfrd/ypxfrd.c.sdnotify	2012-07-12 14:29:03.496853980 +0200
+++ ypserv-2.28/rpc.ypxfrd/ypxfrd.c	2012-07-12 14:29:03.508854082 +0200
@@ -458,6 +458,13 @@ main (int argc, char **argv)
       alarm (_RPCSVC_CLOSEDOWN);
     }
 
+  /* If we use systemd as an init system, we may want to give it 
+     a message, that this daemon is ready to accept connections.
+     At this time, sockets for receiving connections are already 
+     created, so we can say we're ready now. It is a nop if we 
+     don't use systemd. */
+  announce_ready();
+
   svc_run();
   log_msg("svc_run returned");
   unlink (_YPXFRD_PIDFILE);
diff -up ypserv-2.28/ypserv/Makefile.am.sdnotify ypserv-2.28/ypserv/Makefile.am
--- ypserv-2.28/ypserv/Makefile.am.sdnotify	2009-04-02 15:10:19.000000000 +0200
+++ ypserv-2.28/ypserv/Makefile.am	2012-07-12 14:30:15.628494608 +0200
@@ -22,7 +22,7 @@ sbin_PROGRAMS = ypserv
 
 ypserv_SOURCES = ypserv.c server.c ypserv_xdr.c reg_slp.c
 
-ypserv_LDADD =  @PIE_LDFLAGS@ $(top_builddir)/lib/libyp.a @LIBDBM@ @LIBSLP@
+ypserv_LDADD =  @PIE_LDFLAGS@ $(top_builddir)/lib/libyp.a @LIBDBM@ @LIBSLP@ $(LIBSYSTEMD_DAEMON)
 ypserv_CFLAGS = @PIE_CFLAGS@
 
 if ENABLE_REGENERATE_MAN
diff -up ypserv-2.28/ypserv/ypserv.c.sdnotify ypserv-2.28/ypserv/ypserv.c
--- ypserv-2.28/ypserv/ypserv.c.sdnotify	2012-07-12 14:29:03.498853997 +0200
+++ ypserv-2.28/ypserv/ypserv.c	2012-07-12 14:29:03.509854091 +0200
@@ -586,6 +586,13 @@ main (int argc, char **argv)
     register_slp ();
 #endif
 
+  /* If we use systemd as an init system, we may want to give it 
+     a message, that this daemon is ready to accept connections.
+     At this time, sockets for receiving connections are already 
+     created, so we can say we're ready now. It is a nop if we 
+     don't use systemd. */
+  announce_ready();
+
 #if 0
   mysvc_run ();
 #else