ethernet connection lwip stm32

[tıbtıbonline]

netif_add(&gnetif, &ipaddr, &netmask, &gw, NULL, ðernetif_init, &tcpip_input);
while(1){
netif_set_default(&gnetif);

if (netif_is_link_up(&gnetif))
{ netif_set_up(&gnetif);
break;
}
else
{  netif_set_down(&gnetif);
}netif_set_link_callback(&gnetif, ethernet_link_status_updated);
}

I am using open source ethernet code and i am having trouble while connecting. Also when I connect i see my desired output with ARPlines does that mean my connection is lost than connected again or is it just for affirmation for the connection