diff --git a/server.go b/server.go
index 81d5cdf..8fc1409 100644
--- a/server.go
+++ b/server.go
@@ -43,13 +43,13 @@ func (s *server) Start() error {
 	s.sh.Validate()
 
 	if s.stopChan != nil {
-		panic("Server: server is already running. Stop it before starting it again")
+		return fmt.Errorf("Server: server is already running. Stop it before starting it again")
 	}
 	var err error
 	s.ctx = s.sh.ServerContext()
 
 	if err = s.sh.Init(s.ctx); nil != err {
-		logging.Logger().Panic(fmt.Sprintf("Server: Initialization of server has been failed %v", err))
+		return fmt.Errorf("Server: Initialization of server has been failed %v", err)
 	}
 
 	if s.listener, err = s.sh.Listen(s.ctx); nil != err {
@@ -66,7 +66,8 @@ func (s *server) Start() error {
 
 func (s *server) Stop() {
 	if s.stopChan == nil {
-		panic("Server: server must be started before stopping it")
+		logging.Logger().Warn("Server: server must be started before stopping it")
+		return
 	}
 	close(s.stopChan)
 	s.stopWg.Wait()