LinuxQuestions.org - Question on Pinging a address ,how testing sites get away with it and just making a request for service.

- Linux - General (https://www.linuxquestions.org/questions/linux-general-1/)

- - Question on Pinging a address ,how testing sites get away with it and just making a request for service. (https://www.linuxquestions.org/questions/linux-general-1/question-on-pinging-a-address-how-testing-sites-get-away-with-it-and-just-making-a-request-for-service-4175677306/)

Question on Pinging a address ,how testing sites get away with it and just making a request for service.

I managed to ask the entire question I think in the title of this thread.Lol. I always wondered how websites that will ping other servers in online test get away with doing this. Do they have an arrangement with their ISP? Also ,what if you just run a series trying services on all of the common ports? Wouldn't this achieve the same thing as a ping if the tested computer did not respond?

Thanks for your expertise!

Quote:

Originally Posted by theKbStockpiler (Post 6135919)

I don't know, but the ISPs I have been using so far let me use ping without any special arrangement:

Code:

$ ping 1.1.1.1

PING 1.1.1.1 (1.1.1.1): 56 data bytes

64 bytes from 1.1.1.1: icmp_seq=0 ttl=58 time=7.402 ms

64 bytes from 1.1.1.1: icmp_seq=1 ttl=58 time=7.266 ms

64 bytes from 1.1.1.1: icmp_seq=2 ttl=58 time=7.381 ms

--- 1.1.1.1 ping statistics ---

3 packets transmitted, 3 packets received, 0% packet loss

round-trip min/avg/max/stddev = 7.266/7.350/7.402/0.060 ms

Quote:

Also ,what if you just run a series trying services on all of the common ports? Wouldn't this achieve the same thing as a ping if the tested computer did not respond?

If the tested computer doesn't respond, the first question I have is: To what does it not respond? Ping does not necessarily answer the question.

Ping sends special network packets named ICMP echo requests. If the destination device is configured to respond to such requests, it will send ICMP echo replies back.

"Trying services on all of the common ports" is also known as "port scanning". You check if the destination device reacts to attempts to create a connection on a range of TCP or UDP ports. Since this is commonly done by crackers who find a weakness in a system, it is absolutely not recommended to scan ports of servers without the owners' permission. You may quickly end up on a black list.

In any case, a successful ping proves that the other side exists and there is connectivity. If you don't receive replies, either the destination device doesn't exist, or there is no connectivity (might be temporary), or the device is configured not to reply. If you receive replies to some of your requests, the connection might be unreliable. A port scan that yields a reaction also proves that the device in question exists and can be connected to, but it also tells you if it blocks ports and if it listens for requests on ports.

In short, ping and port scans are different tools for different purposes.

Maybe those site use a dummy IP to do a ping sweep, able to capture the response and just dispose the IP once they got what they need. :)

Search the web for Nmap,and see the features of what it does.

I think the premise of the question is, as my old boss would have said, "in error."

Ping is a standard internet protocol used for testing purposes. The same can be said for traceroute, whois, dig, and others.

I use ping whenever I have to test whether my connection is working properly. For example, if a website is not responding, I may ping yahoo.com just to make sure the problem is not on my end.

I'm not "getting away" with anything. I'm testing.

This is not to say that all uses of ping and similar protocols are always innocent, but I think presuming them to be somehow inherently nefarious is, er, presumptuous.