Hi, thank you all for the responses.
Michael, that sounds exactly as what we see. >From the logs that we started to acquire some 10 days ago, we actually see two different IP addresses in a case where just one is returned 132.248.30.3 (105x) 189.215.244.242 (15x) So, we know the most probable reason for this issue. It seems to me that this could be a problem in multiple countries as well. May I suggest to rather return generic servers in Mexico for now? We will use North American pool in this datacenter instead. Regards Jiri Horky On 11/10/2015 07:08 AM, Michael Meier wrote: > On 11/10/2015 01:31 AM, Mouse wrote: >> The example you cite gives an address of 132.248.30.3. This address is >> actually xalli.cie.unam.mx. >> My best guess - given the very limited information I have - is that you >> are dealing with a provider intercepting your DNS requests and >> returning forged responses, probably on the assumption that you are a >> mass-market end user trying to look at Web pages. If cie.unam.mx is >> related to the provider you get your Mexican connectivity from, my >> estimate of the chance that this is the explanation goes up >> substantially. > The estimate of the chance goes down substantially again when you > realize that the IP returned actually is a valid ntp pool server. Would > such an asshole-ISP actually provide a pool service? i think not. > > http://www.pool.ntp.org/zone/mx seems to have the answer: "There are 0 > active servers in this zone". There actually seems to be only one > ntppool server in Mexico. And that one drops out in certain intervals, > possibly because it gets way too much traffic. > So what likely happens is that you get that one server while its score > is high enough. It then drops out because it essentially gets DDoSed by > the requests from all of Mexico. With 0 usable servers remaining in the > .mx zone, the pool system then chooses random servers from all over the > world. When traffic abates enough, that the one MX server answers again, > so its score increases again, and this starts over again. _______________________________________________ pool mailing list [email protected] http://lists.ntp.org/listinfo/pool
