diff --git a/server/Makefile b/server/Makefile
index 44b79665d..88f35adbb 100644
--- a/server/Makefile
+++ b/server/Makefile
@@ -1,7 +1,7 @@
 TARGETS = server send random receive test
 
 # Common dependencies for all binaries
-OBJS = socket.o if.o utils.o msg.o node.o cfg.o tc.o hooks.o list.o path.o hist.o
+OBJS = socket.o if.o utils.o msg.o node.o cfg.o tc.o hooks.o list.o path.o hist.o log.o
 
 VPATH = src
 
diff --git a/server/include/log.h b/server/include/log.h
new file mode 100644
index 000000000..5baf35b13
--- /dev/null
+++ b/server/include/log.h
@@ -0,0 +1,70 @@
+#ifndef _LOG_H_
+#define _LOG_H_
+
+#ifdef __GNUC__
+ #define INDENT		int __attribute__ ((__cleanup__(log_outdent), unused)) _old_indent = log_indent(1);
+#else
+ #define INDENT		;
+#endif
+
+/** Global debug level used by the debug() macro.
+ * It defaults to V (defined by the Makefile) and can be
+ * overwritten by the 'debug' setting in the config file.
+ */
+extern int _debug;
+
+/** The log level which is passed as first argument to print() */
+enum log_level {
+	DEBUG,
+	INFO,
+	WARN,
+	ERROR
+};
+
+int log_indent(int levels);
+
+void log_outdent(int *);
+
+/** Reset the wallclock of debugging outputs */
+void log_reset();
+
+/** Logs variadic messages to stdout.
+ *
+ * @param lvl The log level
+ * @param fmt The format string (printf alike)
+ */
+void log_print(enum log_level lvl, const char *fmt, ...)
+	__attribute__ ((format(printf, 2, 3)));
+
+/** Printf alike debug message with level. */
+#define debug(lvl, msg, ...) do if (lvl <= _debug) log_print(DEBUG, msg, ##__VA_ARGS__); while (0)
+
+/** Printf alike info message. */
+#define info(msg, ...) do log_print(INFO, msg, ##__VA_ARGS__); while (0)
+
+/** Printf alike warning message. */
+#define warn(msg, ...) do log_print(WARN, msg, ##__VA_ARGS__); while (0)
+
+/** Print error and exit. */
+#define error(msg, ...) do { \
+		log_print(ERROR, msg, ##__VA_ARGS__); \
+		die(); \
+	} while (0)
+
+/** Print error and strerror(errno). */
+#define serror(msg, ...) do { \
+		log_print(ERROR, msg ": %s", ##__VA_ARGS__, strerror(errno)); \
+		die(); \
+	} while (0)
+
+/** Print configuration error and exit. */
+#define cerror(c, msg, ...) do { \
+		log_print(ERROR, msg " in %s:%u", ##__VA_ARGS__, \
+			(config_setting_source_file(c)) ? \
+			 config_setting_source_file(c) : "(stdio)", \
+			config_setting_source_line(c)); \
+		die(); \
+	} while (0)
+
+#endif /* _LOG_H_ */
+
diff --git a/server/include/path.h b/server/include/path.h
index e113bc69a..4195855c7 100644
--- a/server/include/path.h
+++ b/server/include/path.h
@@ -39,14 +39,13 @@ struct path
 	double rate;
 
 	/** A pointer to the last received message */
-	struct msg *last;
+	struct msg *current;
+	/** A pointer to the previously received message */
+	struct msg *previous;
 	
 	/** Counter for received messages according to their sequence no displacement */
 	struct hist histogram;
 
-	/** Last known message number */
-	unsigned int sequence;
-
 	/** Counter for sent messages to all outgoing nodes */
 	unsigned int sent;
 	/** Counter for received messages from all incoming nodes */
diff --git a/server/include/utils.h b/server/include/utils.h
index dc4d2e8f3..fce60c599 100644
--- a/server/include/utils.h
+++ b/server/include/utils.h
@@ -13,6 +13,9 @@
 #include <errno.h>
 #include <sched.h>
 #include <string.h>
+#include <sys/types.h>
+
+#include "log.h"
 
 #ifdef __GNUC__
  #define EXPECT(x, v)	__builtin_expect(x, v)
@@ -69,34 +72,16 @@
 				b = tmp; \
 			} while(0)
 
-/** The log level which is passed as first argument to print() */
-enum log_level { DEBUG, INFO, WARN, ERROR };
-
 /* Forward declarations */
 struct settings;
 struct timespec;
 
-/* These global variables allow changing the output style and verbosity */
-extern int _debug;
-extern int _indent;
-
-void outdent(int *old);
-
-#ifdef __GNUC__
- #define INDENT		int __attribute__ ((__cleanup__(outdent), unused)) _old_indent = _indent++;
-#else
- #define INDENT		;
-#endif
-
-/** Reset the wallclock of debugging outputs */
-void epoch_reset();
-
-/** Logs variadic messages to stdout.
- *
- * @param lvl The log level
- * @param fmt The format string (printf alike)
+/** The main thread id.
+ * This is used to notify the main thread about
+ * the program termination.
+ * See error() macros.
  */
-void print(enum log_level lvl, const char *fmt, ...);
+extern pthread_t _mtid;
 
 /** Safely append a format string to an existing string.
  *
@@ -123,9 +108,12 @@ double timespec_delta(struct timespec *start, struct timespec *end);
 /** Get period as timespec from rate */
 struct timespec timespec_rate(double rate);
 
-/** A system(2) emulator with popen/pclose(2) and proper output handling */
+/** A system(2) emulator with popen / pclose(2) and proper output handling */
 int system2(const char* cmd, ...);
 
+/** Call quit() in the main thread. */
+void die();
+
 /** Check assertion and exit if failed. */
 #define assert(exp) do { \
 	if (EXPECT(!exp, 0)) { \
@@ -134,43 +122,5 @@ int system2(const char* cmd, ...);
 		exit(EXIT_FAILURE); \
 	} } while (0)
 
-/** Printf alike debug message with level. */
-#define debug(lvl, msg, ...) do { \
-	if (lvl <= _debug) \
-		print(DEBUG, msg, ##__VA_ARGS__); \
-	} while (0)
-
-/** Printf alike info message. */
-#define info(msg, ...) do { \
-		print(INFO, msg, ##__VA_ARGS__); \
-	} while (0)
-
-/** Printf alike warning message. */
-#define warn(msg, ...) do { \
-		print(WARN, msg, ##__VA_ARGS__); \
-	} while (0)
-
-/** Print error and exit. */
-#define error(msg, ...) do { \
-		print(ERROR, msg, ##__VA_ARGS__); \
-		exit(EXIT_FAILURE); \
-	} while (0)
-
-/** Print error and strerror(errno). */
-#define serror(msg, ...) do { \
-		print(ERROR, msg ": %s", ##__VA_ARGS__, \
-			strerror(errno)); \
-		exit(EXIT_FAILURE); \
-	} while (0)
-
-/** Print configuration error and exit. */
-#define cerror(c, msg, ...) do { \
-		print(ERROR, msg " in %s:%u", ##__VA_ARGS__, \
-			(config_setting_source_file(c)) ? \
-			 config_setting_source_file(c) : "(stdio)", \
-			config_setting_source_line(c)); \
-		exit(EXIT_FAILURE); \
-	} while (0)
-
 #endif /* _UTILS_H_ */
 
diff --git a/server/src/log.c b/server/src/log.c
new file mode 100644
index 000000000..c41c858d3
--- /dev/null
+++ b/server/src/log.c
@@ -0,0 +1,69 @@
+#include <stdio.h>
+#include <time.h>
+
+#include "log.h"
+#include "utils.h"
+
+int _debug = V;
+
+static struct timespec epoch;
+
+#ifdef __GNUC__
+static __thread int indent = 0;
+
+/** Get thread-specific pointer to indent level */
+int log_indent(int levels)
+{
+	int old = indent;
+	indent += levels;
+	return old;
+}
+
+void log_outdent(int *old)
+{
+	indent = *old;
+}
+#endif
+
+void log_reset()
+{
+	clock_gettime(CLOCK_REALTIME, &epoch);
+}
+
+void log_print(enum log_level lvl, const char *fmt, ...)
+{
+	struct timespec ts;
+	char buf[512] = "";
+
+	va_list ap;
+
+	/* Timestamp */
+	clock_gettime(CLOCK_REALTIME, &ts);
+	strap(buf, sizeof(buf), "%8.3f ", timespec_delta(&epoch, &ts));
+
+	/* Severity */
+	switch (lvl) {
+		case DEBUG: strap(buf, sizeof(buf), BLD("%-5s "), GRY("Debug")); break;
+		case INFO:  strap(buf, sizeof(buf), BLD("%-5s "),     "     " ); break;
+		case WARN:  strap(buf, sizeof(buf), BLD("%-5s "), YEL(" Warn")); break;
+		case ERROR: strap(buf, sizeof(buf), BLD("%-5s "), RED("Error")); break;
+	}
+
+	/* Indention */
+#ifdef __GNUC__
+	for (int i = 0; i < indent; i++)
+		strap(buf, sizeof(buf), GFX("\x78") " ");
+	strap(buf, sizeof(buf), GFX("\x74") " ");
+#endif
+
+	/* Format String */
+	va_start(ap, fmt);
+	vstrap(buf, sizeof(buf), fmt, ap);
+	va_end(ap);
+	
+	/* Output */
+#ifdef ENABLE_OPAL_ASYNC
+	OpalPrint("S2SS: %s\n", buf);
+#endif
+	fprintf(stderr, "\r%s\n", buf);
+}
diff --git a/server/src/opal.c b/server/src/opal.c
index 11da0d17c..f97e06c0c 100644
--- a/server/src/opal.c
+++ b/server/src/opal.c
@@ -153,7 +153,7 @@ int opal_read(struct node *n, struct msg *m)
 			state = OpalGetAsyncModelState();
 			if ((state == STATE_RESET) || (state == STATE_STOP)) {
 				info("OpalGetAsyncModelState(): Model stopped or resetted!");
-				exit(0);
+				die();
 			}
 
 			return -1; // FIXME: correct return value
@@ -195,7 +195,7 @@ int opal_read(struct node *n, struct msg *m)
 	state = OpalGetAsyncModelState();
 	if ((state == STATE_RESET) || (state == STATE_STOP)) {
 		info("OpalGetAsyncModelState(): Model stopped or resetted!");
-		exit(0);
+		die();
 	}
 
 	return 0;
@@ -213,7 +213,7 @@ int opal_write(struct node *n, struct msg *m)
 	state = OpalGetAsyncModelState();
 	if ((state == STATE_RESET) || (state == STATE_STOP)) {
 		info("OpalGetAsyncModelState(): Model stopped or resetted!");
-		exit(0);
+		die();
 	}
 
 	OpalSetAsyncRecvIconStatus(m->sequence, o->recv_id);	/* Set the Status to the message ID */
diff --git a/server/src/server.c b/server/src/server.c
index ce0d7e3b2..f352f4b86 100644
--- a/server/src/server.c
+++ b/server/src/server.c
@@ -38,7 +38,7 @@ struct settings settings;
 config_t config;
 
 static void quit()
-{ _indent = 0;
+{
 	info("Stopping paths:");
 	FOREACH(&paths, it)
 		path_stop(it->path);
@@ -103,7 +103,6 @@ void signals_init()
 	sigemptyset(&sa_quit.sa_mask);
 	sigaction(SIGTERM, &sa_quit, NULL);
 	sigaction(SIGINT, &sa_quit, NULL);
-	atexit(&quit);
 }
 
 void usage(const char *name)
@@ -118,11 +117,13 @@ void usage(const char *name)
 	printf("Simulator2Simulator Server %s (built on %s, %s)\n",
 		BLU(VERSION), MAG(__DATE__), MAG(__TIME__));
 	
-	exit(EXIT_FAILURE);
+	die();
 }
 
 int main(int argc, char *argv[])
 {
+	_mtid = pthread_self();
+
 	/* Check arguments */
 #ifdef ENABLE_OPAL_ASYNC
 	if (argc != 2 && argc != 4)
@@ -130,8 +131,7 @@ int main(int argc, char *argv[])
 	if (argc != 2)
 #endif
 		usage(argv[0]);
-	
-	epoch_reset();
+
 	info("This is Simulator2Simulator Server (S2SS) %s (built on %s, %s, debug=%d)",
 		BLD(YEL(VERSION)), BLD(MAG(__DATE__)), BLD(MAG(__TIME__)), _debug);
 
@@ -196,7 +196,7 @@ int main(int argc, char *argv[])
 	else
 		pause();
 
-	/* Note: quit() is called by exit handler! */
+	quit();
 
 	return 0;
 }
diff --git a/server/src/utils.c b/server/src/utils.c
index 4abf4d686..c0515cccf 100644
--- a/server/src/utils.c
+++ b/server/src/utils.c
@@ -12,8 +12,8 @@
 #include <errno.h>
 #include <unistd.h>
 #include <netdb.h>
-#include <time.h>
 #include <math.h>
+#include <signal.h>
 
 #ifdef ENABLE_OPAL_ASYNC
 #define RTLAB
@@ -24,20 +24,11 @@
 #include "cfg.h"
 #include "utils.h"
 
-/* This global variable contains the debug level for debug() and assert() macros */
-int _debug = V;
-int _indent = 0;
+pthread_t _mtid;
 
-struct timespec epoch;
-
-void outdent(int *old)
+void die()
 {
-	_indent = *old;
-}
-
-void epoch_reset()
-{
-	clock_gettime(CLOCK_REALTIME, &epoch);
+	pthread_kill(_mtid, SIGTERM);
 }
 
 int strap(char *dest, size_t size, const char *fmt,  ...)
@@ -59,42 +50,6 @@ int vstrap(char *dest, size_t size, const char *fmt, va_list ap)
 	return vsnprintf(dest + len, size - len, fmt, ap);
 }
 
-void print(enum log_level lvl, const char *fmt, ...)
-{
-	struct timespec ts;
-	char buf[512] = "";
-
-	va_list ap;
-
-	/* Timestamp */
-	clock_gettime(CLOCK_REALTIME, &ts);
-	strap(buf, sizeof(buf), "%8.3f ", timespec_delta(&epoch, &ts));
-
-	/* Severity */
-	switch (lvl) {
-		case DEBUG: strap(buf, sizeof(buf), BLD("%-5s "), GRY("Debug")); break;
-		case INFO:  strap(buf, sizeof(buf), BLD("%-5s "),     "     " ); break;
-		case WARN:  strap(buf, sizeof(buf), BLD("%-5s "), YEL(" Warn")); break;
-		case ERROR: strap(buf, sizeof(buf), BLD("%-5s "), RED("Error")); break;
-	}
-
-	/* Indention */
-	for (int i = 0; i < _indent; i++)
-		strap(buf, sizeof(buf), GFX("\x78") " ");
-	strap(buf, sizeof(buf), GFX("\x74") " ");
-
-	/* Format String */
-	va_start(ap, fmt);
-	vstrap(buf, sizeof(buf), fmt, ap);
-	va_end(ap);
-	
-	/* Output */
-#ifdef ENABLE_OPAL_ASYNC
-	OpalPrint("S2SS: %s\n", buf);
-#endif
-	fprintf(stderr, "%s\n", buf);
-}
-
 cpu_set_t to_cpu_set(int set)
 {
 	cpu_set_t cset;