Multiple ping requests to several hosts in parallel

[Hermarcel]

I need to ping several hosts in parallel from an event callback function. I cannot figure out how to do this. I created an array:

Pinger pinger[5]; // as global, [0] is unused

And tried to issue the pings in a loop within an event callback:

IPAddress IPtoPing(172,16,172,0);
for(i = 1; i <= 4; i++) {`
    IPtoPing[3] = i;
    pinger[i].OnEnd([](const PingerResponse& response)
    {
        Serial.printf("IP address: %s\n",  response.DestIPAddress.toString().c_str());
        return(true);
    });
    
    if(pinger[i].Ping(IPtoPing) == false) {
        // Error
    }
}

I would expect a ping being issued to ip's 192.168.0.1 thru 192.168.0.4, each leading to it's own callback and it's ip address being printed upon Serial. I do see the ARP and ICMP frames correctly in Wireshark. The OnEnd callback, however, is called only once, only for the last ip in the loop.

Am I doing something wrong? Am I missing something?

[Hermarcel]

To answer my own question: Give the frames of each ping-request their own id by calling "SetPacketsId()"