Current Pool Capacity?


#1

I was browsing the main site and came across a note (on the vendor page I believe) that said the Pool currently serves between 5-15 million systems. I think that number is grossly underestimated… On my server alone (Pool Settings: 100Mb / US) I will see anywhere between 1-2 million unique IPs per day…

Pool DNS shows around 30,000 queries per second… Assume 1/3 would be full NTP clients with the standard 4 pool config lines (rest would be more basic SNTP clients making single requests), would calculate (guessing) around 22,500 unique IPs per second, round down to 20k figuring some have to be bad queries or redundant, and you still get 72 million per hour… Who knows per day… Would have to figure some get power cycled, or re-query a few times for fresh pool servers, or if it’s just an hourly cron job to update time, etc…

Would be interesting to do some logging on the DNS server to figure out unique IPs (and possibly also geo-tagging to group by country). I bet too numbers could be aggregated on the vendor zones to see who are the top users.

I wonder how much NTP traffic Microsoft, Google, and NIST get too…


#2

Patches are welcome! https://github.com/abh/ntppool

It would be fun to have some opt-in statistics that each operator could run and contribute data to a central repository to better estimate the traffic (and sooner catch abnormalities like the snapchat incident some years ago).

I’m pretty sure we well surpassed the NIST servers about a decade ago.


#3

Ah yes, I keep forgetting it’s on github, I’ll look over everything and see what I can make sense of…

I’m also curious more about the DNS system which I hope the code is in there… Even though I’m in the US, I get a LOT of traffic from Asia (mostly China)… Due to distance you would think Europe would get any Asia overflow as you would kind of want to group clients & servers as close as physically possible (without overloading a pool).


#4

Hi Ask,

NTF is talking about putting up some ntp traffic numbers. Have you spoken to Harlan about your idea?

Steve


#5

I re-enabled logging on my server yesterday and here’s some stats over the past ~24 hours… (US Pool, 100Mb Setting)…

Here’s the top 25 countries sorted by # of unique IPs, they represent about 97% of all the queries.

Interesting to see how Canada & China have about the same # of unique IPs, yet China is making about 10x more requests… China also seems to be behaving decently these past 24 hours… There is usually at least a couple times a week I’ll get bombarded from there for brief periods, either spoofed requests or the great firewall going nuts, or something.

Also interesting to see how many queries come from Europe, when their pool is almost 3x larger than NA???

Allowed/Dropped is based on firewall rulesets, hashlimit allows each unique IP a burst of 10 packets + 6/min, anything beyond that rate is dropped.

Country IP Addrs Q Allow Q Drop % of IP % Tot Q Allow % Tot Q Drop % Dropped
US 1,912,853 24,731,414 1,466,083 68.32% 77.74% 88.99% 5.93%
CA 99,393 252,387 15,457 3.55% 0.79% 0.94% 6.12%
CN 98,746 2,435,410 11,283 3.53% 7.66% 0.68% 0.46%
RU 67,612 895,278 14,176 2.41% 2.81% 0.86% 1.58%
BR 65,073 228,461 18,470 2.32% 0.72% 1.12% 8.08%
IN 60,302 240,023 3,560 2.15% 0.75% 0.22% 1.48%
DO 39,520 115,242 3,854 1.41% 0.36% 0.23% 3.34%
MX 35,446 126,336 14,355 1.27% 0.40% 0.87% 11.36%
DE 27,080 502,659 18,600 0.97% 1.58% 1.13% 3.70%
AR 24,200 62,555 1,448 0.86% 0.20% 0.09% 2.31%
GB 22,322 582,827 5,019 0.80% 1.83% 0.30% 0.86%
GT 22,284 115,122 2,988 0.80% 0.36% 0.18% 2.60%
SV 20,892 69,787 4,386 0.75% 0.22% 0.27% 6.28%
PA 15,597 47,642 4,434 0.56% 0.15% 0.27% 9.31%
HN 14,981 56,581 2,145 0.54% 0.18% 0.13% 3.79%
NI 12,329 36,596 534 0.44% 0.12% 0.03% 1.46%
MA 11,284 22,196 80 0.40% 0.07% 0.00% 0.36%
FR 11,033 53,330 4,428 0.39% 0.17% 0.27% 8.30%
TR 9,959 27,684 288 0.36% 0.09% 0.02% 1.04%
ES 9,457 34,010 7,854 0.34% 0.11% 0.48% 23.09%
JP 9,125 94,379 807 0.33% 0.30% 0.05% 0.86%
JM 9,122 30,894 426 0.33% 0.10% 0.03% 1.38%
UA 8,519 64,610 1,162 0.30% 0.20% 0.07% 1.80%
CO 7,905 18,668 548 0.28% 0.06% 0.03% 2.94%

#6

The DNS server code is at https://github.com/abh/geodns

Eastern Asia is closer to the US than to Europe. Mostly Asia is just plain underserved though with most countries having many more clients than servers. The same is true for many countries in Europe and some in North America.


#7

Counting clients on the global scale seems difficult, but I think it should be at least possible to estimate the total amount of NTP traffic.

We just need some data for at least one NTP server in each country zone. We need the average packet rate (e.g. over day or week) and the speed setting. From the distribution of servers in DNS responses we can estimate the average speed setting for that zone and the total amount of NTP traffic.

I was able to do that for a small number of zones for which I have my own data or found information from other people here. For example, in the US zone there seems to be about 400000 requests per second. I was expecting more.

I put the data in a spreadsheet.

If you are willing to share data for servers in other zones, I can add it to the table. I need the average observed request rate separately for IPv4/IPv6 and speed setting. I may also need the IP address if no server in the zone is using the maximum speed (1Gb), or the number of servers is so small that the speed setting has little effect, which I assume is a common case in the underserved zones. The server should be in just one country zone (not helping other zones).


#8

Interesting chart… Looking at my traffic graph, my 100Mb US IPv4 server is showing an average of about 370 p/s, so that’s right in line at 1/10th your 1Gb server. I would say the load balancing algorithm is working pretty good, lol.

How did you determine average server speed for the various zones?


#9

By observing how frequently are specific servers returned by the pool DNS server. If a 1Gb server in the US zone is returned in about 0.95% of DNS responses and there are 527 servers, the average speed should be 1000Mb/0.95%/527 = 200 Mb.

I’m not sure how accurate these numbers really are. I hope they are good to at least an order of magnitude.