diff --git a/Makefile b/Makefile
index 0b82deb..cae4bc0 100644
--- a/Makefile
+++ b/Makefile
@@ -1,5 +1,17 @@
 run:
 	go run src/main.go -p 5053 -d "127.0.0.1:5059"
 
+test-ip:
+	go run src/main.go -p 5053 -d "127.0.0.1:5059,localhost:5059"
+
+test-port:
+	go run src/main.go -p 5053 -d "127.0.0.1:5059,127.0.0.1:as"
+
+test-port-max:
+	go run src/main.go -p 5053 -d "127.0.0.1:5059,127.0.0.1:65537"
+
+test-port-endpoint:
+	go run src/main.go -p 5053 -d "127.0.0.1:9001/bid_request"
+
 build:
 	go build -o bin/simple-choose-ad src/main.go
diff --git a/src/client_server/validators.go b/src/client_server/validators.go
index d1befd0..a5f9077 100644
--- a/src/client_server/validators.go
+++ b/src/client_server/validators.go
@@ -10,6 +10,8 @@ import (
 	"strings"
 )
 
+const MAX_PORT_NUM = 65535
+
 // Returns false if ipv4 `correct`.
 func wrongIPAddresFormat(ipv4 string) bool {
 	re, err := regexp.Compile(`^\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}$`)
@@ -24,6 +26,8 @@ func throwHTTPError(err_text string, code int, w *http.ResponseWriter) {
 	log.Printf("Error: %d %v\n", code, err_text)
 }
 
+// Wait string in format "10.10.10.10:8080", where `10.10.10.10` IPv4,
+// and `8080` port. If ip or port has wrong format, returns error.
 func ParsePartnersAddress(ipAndPort string) (string, int64, error) {
 	var err error
 	iap := strings.Split(ipAndPort, ":")
@@ -33,6 +37,14 @@ func ParsePartnersAddress(ipAndPort string) (string, int64, error) {
 		err = errors.New(fmt.Sprintf("Wrong ip address format in partner ip: %v", ip))
 	}
 
-	port, _ := strconv.ParseInt(iap[1], 10, 32)
+	port, e := strconv.ParseInt(iap[1], 10, 32)
+	if e != nil {
+		err = errors.New(fmt.Sprintf("Wrong port format in partner ip: %v", e))
+	}
+
+	if port > MAX_PORT_NUM {
+		err = errors.New(fmt.Sprintf("Wrong port in partner ip: grater than %v", MAX_PORT_NUM))
+	}
+
 	return ip, port, err
 }
diff --git a/src/main.go b/src/main.go
index 70652d8..a0dbd6b 100644
--- a/src/main.go
+++ b/src/main.go
@@ -1,16 +1,14 @@
 /*
 Usage:
 
-   sample-choose-ad [flags]
+	sample-choose-ad [flags]
 
 The flags are:
-   -p
-       Listening port
-   -d
-       Adversment partners list in format ip_p1:port,ip_p2:port2...ip_p10:port
-
-
 
+	-p
+	    Listening port
+	-d
+	    Adversment partners list in format ip_p1:port,ip_p2:port2...ip_p10:port
 */
 package main
 
@@ -49,8 +47,7 @@ func main() {
 		ip, port, err := clientserver.ParsePartnersAddress(p)
 
 		if err != nil {
-			log.Println(err)
-			continue
+			log.Fatalln(err)
 		}
 
 		partners = append(partners, customtypes.PartnersAddress{