im new to opc but need to connect with a server.
my colleague told me the server is no Security Policy and Certificate, just a username and password, he is not familiar with this too.

the result is :
enter image description here

And i do connect with the server by UaExpert:
enter image description here
enter image description here

there is my code:

#include "open62541.h"
#include "ros/ros.h"
#include <iostream>

int main() {

    UA_Client *client = UA_Client_new();
    UA_ClientConfig *cc = UA_Client_getConfig(client);

    UA_ClientConfig_setDefault(cc);

    cc->securityMode = UA_MESSAGESECURITYMODE_NONE;

    const char* serverurl = "opc.tcp://server_ip";
    const char* username = "username";
    const char* password = "123";
    UA_StatusCode retval = UA_Client_connectUsername(client, serverurl, username, password);

    if(retval != UA_STATUSCODE_GOOD) {
        UA_Client_delete(client);
        return EXIT_FAILURE;
    }

    UA_LOG_INFO(UA_Log_Stdout, UA_LOGCATEGORY_USERLAND, "Connected!");

    UA_Client_disconnect(client);
    UA_Client_delete(client);
    return retval == UA_STATUSCODE_GOOD ? EXIT_SUCCESS : EXIT_FAILURE;
}

i cant find a solution, so i ask the question
thanks