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I am wondering why, when ping flooding a domain, the ping flood freezes after a couple of seconds then continues and this freeze, unfreeze continues until i stop the ping flood.

When i do the same using the ip it does not freeze. NEVER.

i did for example sudo ping -f IP (It does not freeze)
then i did sudo ping -f DomainName (It freezes after a couple of seconds)

Why does ping flooding an IP not freezes and ping flooding the same place using the domain name does freeze.

EDIT - What i mean about freezing is that the behavior of the ping flood should send a ping and create a dot (.) for each ping but also remove each dot (.) after receiving the echo request. Looks something like this:

.......... <-- This means you just send 10 ping requests.

If the requests are answer, for each request answer a dot is removed. The freeze happens when this is sending or receiving. The dots will stay there frozen, like is not receiving or sending any packets.

For the PING FLOOD. I do not mean in the evil way of flooding a place, i mean in the testing way. To test the performance/speed of the request send and answered of the ping requests. If you send a ping flood to google's IP for about 10 seconds you would have send about 1000 packets.but if you do it to google's domain name (google.com) it will create the freeze am talking about.

IMPORTANT - Do not confuse with flooding a site with ping of death attacks.

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Does it drop packets (Is there a break in the sequence #?) Is there a spike in latency? –  Hyppy Mar 23 '11 at 1:57
    
What do you mean exactly by ping flooding a domain? –  joeqwerty Mar 23 '11 at 2:10
1  
I'm honestly baffled. There shouldn't be a difference, and if the initial few pings are actually being sent out before the pause then it couldn't be a DNS delay. Throw wireshark on and see if there are any actual packets sent before the apparent delay, maybe it is DNS latency and ping is just lying about the first few packets –  Hyppy Mar 23 '11 at 2:31
    
Pleae try it and see what i mean. The packets will freeze after a few seconds using the domain name but not freeze using the IP –  CYREX Mar 23 '11 at 3:08
    
why are you trying to ping flood a domain? –  Zypher Mar 23 '11 at 3:40
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1 Answer 1

up vote 3 down vote accepted

I have the same problem, and after "strace ping -f DomainName" I discovered it tries to resolve IP address to hostname when each packet received. The solution is simple, just add -n parameter to avoid hostname lookup.

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