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ping ya.ru
PING ya.ru (213.180.193.3) 56(84) bytes of data.
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=1 ttl=60 time=97.6 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=2 ttl=60 time=96.6 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=3 ttl=60 time=95.6 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=4 ttl=60 time=94.5 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=5 ttl=60 time=92.6 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=6 ttl=60 time=91.9 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=7 ttl=60 time=90.5 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=8 ttl=60 time=88.6 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=9 ttl=60 time=87.6 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=10 ttl=60 time=86.7 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=11 ttl=60 time=85.6 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=12 ttl=60 time=84.5 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=13 ttl=60 time=82.6 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=14 ttl=60 time=80.6 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=15 ttl=60 time=79.6 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=16 ttl=60 time=77.6 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=17 ttl=60 time=76.5 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=18 ttl=60 time=74.7 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=19 ttl=60 time=73.6 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=20 ttl=60 time=72.6 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=21 ttl=60 time=71.6 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=22 ttl=60 time=70.5 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=23 ttl=60 time=68.7 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=24 ttl=60 time=67.6 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=25 ttl=60 time=67.0 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=26 ttl=60 time=65.6 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=27 ttl=60 time=64.6 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=28 ttl=60 time=63.4 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=29 ttl=60 time=61.6 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=30 ttl=60 time=60.6 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=31 ttl=60 time=59.5 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=32 ttl=60 time=57.6 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=33 ttl=60 time=56.5 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=34 ttl=60 time=54.5 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=35 ttl=60 time=53.6 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=36 ttl=60 time=52.3 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=37 ttl=60 time=50.5 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=38 ttl=60 time=49.5 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=39 ttl=60 time=47.5 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=40 ttl=60 time=45.6 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=41 ttl=60 time=44.6 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=42 ttl=60 time=44.0 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=43 ttl=60 time=42.5 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=44 ttl=60 time=40.5 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=45 ttl=60 time=39.4 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=46 ttl=60 time=37.6 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=47 ttl=60 time=36.5 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=48 ttl=60 time=34.6 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=49 ttl=60 time=33.5 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=50 ttl=60 time=31.6 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=51 ttl=60 time=30.6 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=52 ttl=60 time=29.5 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=53 ttl=60 time=27.5 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=54 ttl=60 time=26.5 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=55 ttl=60 time=24.6 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=56 ttl=60 time=23.5 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=57 ttl=60 time=21.5 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=58 ttl=60 time=19.5 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=59 ttl=60 time=17.6 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=60 ttl=60 time=17.4 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=61 ttl=60 time=15.5 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=62 ttl=60 time=13.4 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=63 ttl=60 time=12.0 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=64 ttl=60 time=10.5 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=65 ttl=60 time=8.57 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=66 ttl=60 time=6.55 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=67 ttl=60 time=4.51 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=68 ttl=60 time=2.68 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=69 ttl=60 time=1.55 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=70 ttl=60 time=99.5 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=71 ttl=60 time=97.6 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=72 ttl=60 time=96.7 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=73 ttl=60 time=95.6 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=74 ttl=60 time=93.7 ms

Take a look at "time" field, it decrement from 100 to 0 by 1ms with every packet and after that time = 0 it starts again from 100ms.

My friend rebooted this server, but I would like to now what it could be.

after reboot it's ok:

ping -c 3 ya.ru
PING ya.ru (213.180.193.3) 56(84) bytes of data.
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=1 ttl=60 time=1.71 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=2 ttl=60 time=2.69 ms
64 bytes from www.yandex.ru (213.180.193.3): icmp_req=3 ttl=60 time=2.57 ms

and tracepath has 2 variants:

 tracepath ya.ru -n
 1?: [LOCALHOST]                                         pmtu 1500
 1:  86.62.102.1                                           0.531ms 
 1:  86.62.102.1                                           0.548ms 
 2:  86.62.124.66                                         37.162ms 
 3:  86.62.124.129                                         0.946ms asymm  2 
 4:  193.232.244.93                                        2.492ms asymm  3 
 5:  no reply
 6:  87.250.239.75                                         2.759ms 
 7:  87.250.239.75                                         3.062ms asymm  6 
 8:  no reply
 9:  no reply
10:  no reply
11:  93.158.134.3                                          2.986ms reached
     Resume: pmtu 1500 hops 11 back 58 

or

tracepath ya.ru -n
 1?: [LOCALHOST]                                         pmtu 1500
 1:  86.62.102.1                                           0.670ms 
 1:  86.62.102.1                                           0.601ms 
 2:  86.62.124.66                                          0.858ms 
 3:  86.62.124.129                                         0.978ms asymm  2 
 4:  193.232.244.93                                        2.353ms asymm  3 
 5:  87.250.239.49                                         1.820ms asymm  4 
 6:  no reply
 7:  213.180.193.3                                         3.164ms reached
     Resume: pmtu 1500 hops 7 back 60 
share|improve this question

closed as off-topic by joeqwerty, TheCleaner, Rex, mdpc, Ward Apr 1 '14 at 3:08

This question appears to be off-topic. The users who voted to close gave this specific reason:

  • "Questions must be relevant to professional system administration. Server Fault is dedicated to professional system and network administrators. End user and enthusiast questions are off-topic (contact your system administrator or hire a professional to help you out). Please see the Help Center for more information." – joeqwerty, TheCleaner, Rex, mdpc, Ward
If this question can be reworded to fit the rules in the help center, please edit the question.

    
What does the output of traceroute look like? – 200_success Mar 31 '14 at 9:27
    
As I said before, that server was rebooted, for that momenet there is a ping about 2ms – alterpub Mar 31 '14 at 11:15
    
Also, if you try to debug stuff like that, you should ping/traceroute ip addresses, and not names, as DNS may deliver a different IP each time – MichelZ Mar 31 '14 at 11:32

The roundtrip variations look very unnatural. I don't think those could have been caused by inaccurate timing measurements or by network congestion.

But network simulation hardware and/or software might very well be able to insert synthetical delays. That would be a very useful feature during software development. And the variations you see would not be that hard to introduce with network simulation tools.

Also I guess you haven't really been pinging the server, you think you were pinging. Considering the less than 2ms roundtrip and the speed of light in optical fiber, you can compute a maximum distance between your server and the host you have been pinging. It cannot be more than a few 100 km away.

The TTL is another clue. The packets arrive with a TTL of 60. It is likely they were send with a TTL of 64. That means there is only four routers between you and the node you were pinging.

share|improve this answer
    
usual default ping to ya.ru from me about 2-3ms, there are 6 or 11 hops(by tracepath). – alterpub Mar 31 '14 at 11:13
2  
Some network simulation hardware/software looks like a valid explanation for this, indeed – MichelZ Mar 31 '14 at 11:33
    
i usually get <1ms for servers in the same data center when testing if one of them has some issues. BTw: a few 100km means half of central europe. – Dennis Nolte Apr 4 '14 at 12:56

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