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NTP Pool Reaches 1000 Servers, Needs More

kdawson posted more than 6 years ago | from the if-you-got-the-money-honey-i-got-the-time dept.

The Internet 230

hgerstung writes "This weekend the NTP Pool Project reached the milestone of 1000 servers in the pool. That means that in less than two years the number of servers has doubled. This is happy news, but the 'time backbone' of the Internet, provided for free by volunteers operating NTP servers, requires still more servers in order to cope with the demand. Millions of users are synchronizing their PC's system clock from the pool and a number of popular Linux distributions are using the NTP pool servers as a time source in their default ntp configuration. If you have a static IP address and your PC is always connected to the Internet, please consider joining the pool. Bandwidth is not an issue and you will barely notice the extra load on your machine."

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230 comments

We will control you all! (-1, Troll)

Anonymous Coward | more than 6 years ago | (#20524467)

Sounds kind of like a "voluntary" STORM WORM to me.........

Google (5, Interesting)

Seumas (6865) | more than 6 years ago | (#20524475)

This sounds like a job for Google.

Seriously. They are working to own every other bit of information. Why not "own" the method by which machines maintain time by throwing a thousand machines at it (an insignificant number compared to the 500k or more that make up their own server farm).

Re:Google (1, Insightful)

thegrassyknowl (762218) | more than 6 years ago | (#20524555)

I wanted to submit my PC to the pool but you must have a static IP *grr* I'm not paying more to get a fixed IP address. It's not like I use all of that enormous data allocation or fat pipe. In fact, if I didn't download 100G of pr0nz each month it wouldn't even get 50% used!

Re:Google (1, Informative)

Anonymous Coward | more than 6 years ago | (#20525391)

Uh... how exactly do you propose they work with dynamic IPs?

Re:Google (2, Insightful)

Anonymous Coward | more than 6 years ago | (#20525521)

Uh... how exactly do you propose they work with dynamic IPs?
Dynamic DNS, just like everybody else on dynamic IPs.

Re:Google (2, Informative)

Charles Dodgeson (248492) | more than 6 years ago | (#20524879)

Why not "own" the method by which machines maintain time by throwing a thousand machines at it
A thousand machines all on one bit of network does little good. These need to distributed around the globe.

Re:Google (3, Informative)

Seumas (6865) | more than 6 years ago | (#20524999)

Google's server farms are distributed around the world. both coasts and in between as well as Ireland, Belgium and elsewhere.

Re:Google (0, Flamebait)

PCM2 (4486) | more than 6 years ago | (#20524981)

This sounds like a job for Google. Seriously. They are working to own every other bit of information.

And all your information being "owned" by one commercial organization is a good thing why?

Re:Google (1)

Seumas (6865) | more than 6 years ago | (#20525029)

How are they supposed to track what subversive materials I'm reading or what kind of groups I'm congregating with or who I'm socializing with or what my personal views and beliefs are, otherwise?!

Re:Google (1)

ILuvRamen (1026668) | more than 6 years ago | (#20525813)

oh now we're getting Google involved? For God's sake people, how many servers does it take to tell you what time it is? Isn't it more likely that some of 1000 servers somehow report wrong information instead of one single atomic clock? Seriously, what's wrong with one atomic clock? I hear they're KINDA accurate. I just don't get the point of using tons of servers for it. Is it supposed to compensate for time passing at slightly different rates in different places on Earth or something? Are they concerned that if half the world suddenly blows up that that we'd all not know precisely what time it is? I think that'd be the least of my worries lol. Can someone please explain this whole concept for us?

Re:Google (0)

Anonymous Coward | more than 6 years ago | (#20525959)

A lot of financial transactions, legal disputes and technical things require precise timing. Imagine if your bank used their own clock network that, whoops, accidentally loses a few seconds each day (interest bearing seconds). Later on, someone realises what's happened, and they have to set the clocks forward and pay thousands (if not tens of thousands) of people scores of money in back interest. Or, let's say that you're bidding for that lovely new 1000pc crate of ramen noodles on eBay and you set up an auction snipe - but your PC clock was 30 seconds off, and you bid too late. There are dozens of things which require precise timing.

huh? (5, Interesting)

adamruck (638131) | more than 6 years ago | (#20524477)

"Bandwidth is not an issue and you will barely notice the extra load on your machine."

If that is the case, why do they need more servers?

Re:huh? (3, Informative)

larry bagina (561269) | more than 6 years ago | (#20524615)

latency. The time you get back from the NTP server is the time the server sent the request. The client has to count the time it took to get a response and use that as a fudge factor. More servers means your client can find a closer server and minimize the transport time.

Re:huh? (2, Funny)

Ford Prefect (8777) | more than 6 years ago | (#20524693)

(Argh, crap - tried moderating this 'Interesting' and managed 'Offtopic' instead. Sorry - undoing all my moderation for this article. Please ignore this message!)

Re:huh? (4, Interesting)

ls -la (937805) | more than 6 years ago | (#20525173)

There really should be an "Oops" button after you mod something; I've never done this myself but I've seen at least 2 or 3 of this type of message in the last few days.

Re:huh? (2, Funny)

fuzzix (700457) | more than 6 years ago | (#20525413)

(Argh, crap - tried moderating this 'Interesting' and managed 'Offtopic' instead. Sorry - undoing all my moderation for this article. Please ignore this message!)

I modded this post Off Topic and I meant it!

Oh shit, did I just post?

Re:huh? (5, Informative)

JackHoffman (1033824) | more than 6 years ago | (#20524789)

No, the network time protocol accounts for latency and eliminates its influence almost completely as long as the latency is roughly symmetric, which it usually is for small packets.

Re:huh? (1)

Mistlefoot (636417) | more than 6 years ago | (#20525477)

Latency doesn't seem to be that important to me neither.

I'd like to think that if my computer is say, 100ms off clock time that I won't be much affected.

I can't think of one instance where being off by even a half a minute or so that I would be affected.

Does anyone actually know the answer posed by the OP?

Re:huh? (1)

karnal (22275) | more than 6 years ago | (#20525559)

If you're capturing packets from multiple machines and want to line up the captures, then you need to have accuracy.

If you're using SNMP to log equipment on the network, it helps to have everything as lined up as you can. Now, if you're a company doing this, typically you have your own time server and don't rely on this pool. But there are benefits to some to have more exacting time across all devices.

Re:huh? (1)

spaceboy_ (125500) | more than 6 years ago | (#20525169)

NTP traffic is often not at a constant rate. There a spikes and periodic peaks. More servers in the pool would help spread the load during peaks.

Re:huh? (5, Informative)

mrcaseyj (902945) | more than 6 years ago | (#20525837)

"Bandwidth is not an issue and you will barely notice the extra load on your machine."

If that is the case, why do they need more servers?

If I understand it right bandwidth isn't an issue because they can tailor how much of the pool load goes to your machine. When someone queries the pool their ntp client does a DNS query to pool.ntp.org. The pool's DNS server semi randomly returns the IP address of one of the volunteer servers in the pool. If you tell the pool operators that you have only a little bandwidth then the pool DNS server will only return your IP address say one tenth as often as it does the IPs for the high traffic servers. This allows you to decide how much load you're willing to bear. Even if the pool is overloaded, your machine doesn't have to be.

Mod parent up so volunteers won't be scared off (1)

mrcaseyj (902945) | more than 6 years ago | (#20525983)

I had hoped my comment would be modded up quickly but it hasn't so forgive me for asking that someone mod my parent post up so that volunteers won't be scared off for fear of bandwidth overload. I've already got excellent karma so I'm not asking this for me, I'm asking for the sake of the pool.

load (1, Insightful)

ls -la (937805) | more than 6 years ago | (#20524481)

Bandwidth is not an issue and you will barely notice the extra load on your machine.
I think if their servers can't keep up, you *will* notice the load, at least until enough join.

Re:load (1)

Mr Z (6791) | more than 6 years ago | (#20524545)

Not really. The more time sources you have, the more precise your estimate of the time will be, since you'll be able to cancel out disparate network jitter better.

--Joe

Re:load (5, Informative)

gregbaker (22648) | more than 6 years ago | (#20524557)

Their servers can keep up just fine, or at least the one I run can. My stats show 1GB per month traffic and the ntpd process taking about 1 minute/day of processor time. That has been relatively constant over the year or so the server has been in the pool.

I think this is just a case of more==better. A bigger pool means more people can use their local zone instead of the global zone, the whole system can handle more clients, less load on servers means even more may be willing to join, ...

Seriously, it's not that big a deal. Just thow your server into the pool and forget about it.

Re:load (2, Interesting)

seringen (670743) | more than 6 years ago | (#20524667)

Hear hear That's consistent with what I have on my server - I never feel it and the more pool, the higher accuracy and ability to account for one-time blips of load like if hardware manufacturer hard codes all their routers to check at the very same time - certainly not impossible to imagine considering what's happened to some university NTP pools. I highly recommend joining.

Re:load (1)

Charles Dodgeson (248492) | more than 6 years ago | (#20524699)

I just want to add a "me, too". Collecting the stats and usage reports for my contribution to the pool takes far more resources than actually contributing to the pool. NTP is really light weight. The only "problem" I've seen is that every couple of months, it is useful for me to reset the state of my firewall. I didn't have to do that before joining the pool.

What can happen if a server gets "overloaded" is that the NTP service degrades. NTP sends UDP packets and so if the NTP server has more than it can handle it simply drops some queries. The host machine for the server doesn't show problems in other respects. You really won't notice that NTP service is running (even if overloaded) unless you specifically run some monitoring scripts (which, as I've said, consume far more resources than NTP).

Re:load (1)

buckadude (926560) | more than 6 years ago | (#20524895)

I would love to join, my problem is with my service provider. I use FIOS and if I want a static IP I have to forgo the ability to get TV service at my house. This is a problem for me and i'm sure other users of FIOS. Oh well, perhaps some time in the future?

clarify please (1)

PhreakOfTime (588141) | more than 6 years ago | (#20525649)

Could you clarify that a little more please? Why does getting a static IP remove the option of TV service? I cant see any technical problems for that to be the case, so it must be some oddly written contract.

I would imagine with some deep digging, such a contract would be found to be anti-competitive.

On a side note, its pretty obvious why the state of broadband in the US is what it is. TeleVision is the sacred (cash) cow. Combine this with the strong opposition to any sort of NetNeutrality, and the game these TV/Internet/Phone companies are playing is becoming very clear. Not to mention VERY disturbing.

VMWare? (1)

MikeFM (12491) | more than 6 years ago | (#20525051)

Do they have a VMWare image I can run? Real lite like FreeNAS?

Re:VMWare? (2, Informative)

ask (1258) | more than 6 years ago | (#20525277)

The virtualized servers don't usually keep their own time - or when they do they do a poor job.

Re:VMWare? (1)

MikeFM (12491) | more than 6 years ago | (#20525567)

That's a good point although I only really see the system complain when I'm running 64bit Linux. I've never noticed the time being off in either though. Even if the virtual machine stays synced to the vm host clock it'd still be useful to have the ntp service running in a virtual machine - if the clock isn't off.

So, what are they gonna say when overwhelmed? (1)

nlitement (1098451) | more than 6 years ago | (#20524487)

"Pool's closed"?

Re:So, what are they gonna say when overwhelmed? (0)

Anonymous Coward | more than 6 years ago | (#20524649)

due to aids?

Re:So, what are they gonna say when overwhelmed? (0)

Anonymous Coward | more than 6 years ago | (#20525037)

anon! brother!

didnt they think of this? (1)

wizardforce (1005805) | more than 6 years ago | (#20524531)

Bandwidth is not an issue and you will barely notice the extra load on your machine. I think if their servers can't keep up, you *will* notice the load, at least until enough join.
do they have no way of routing/limiting traffic so that it isn't normally noticeable?

Re:didnt they think of this? (3, Insightful)

ask (1258) | more than 6 years ago | (#20524551)

The NTP protocol gives very limited ways of limiting it, so short of just closing down if we can't add servers as fast as traffic is added, no - there isn't much we can do.

The vendor program [ntp.org] is one way we're trying to get more control, but all else being equal - more servers helps.

Unless netgear hears about you (0)

Anonymous Coward | more than 6 years ago | (#20524579)

"Bandwidth is not an issue and you will barely notice the extra load on your machine."

And then Netgear will go and hard code your ip address into one of it's dumbass products, and you're entire network will be crushed offline... permanently.

Re:Unless netgear hears about you (1)

shawn443 (882648) | more than 6 years ago | (#20524663)

Netgear products, built in permanent network offline crushes, for thousands of addresses. I even googled "Netgear will go and hard code your ip address into one of it's dumbass products". Nothing really came up.

Re:Unless netgear hears about you (2, Informative)

Anonymous Coward | more than 6 years ago | (#20524851)

Your google fu sucks, grasshopper.

NTP abuse [wikipedia.org]

NTP Isn't Accurate (0, Troll)

Anonymous Coward | more than 6 years ago | (#20524591)

The problem with these time servers is that many of them are not accurate. I use Ubuntu and when looking through all of the time servers, nearly all of them are off by as much as three minutes. I use http://time.gov/ [time.gov] as my source for accurate time. The atomic clocks are run by the Department of Commerce agency, the National Institute of Standards and Technology (NIST), and its military counterpart, the U. S. Naval Observatory (USNO). Readings from the clocks of these agencies contribute to world time, called Coordinated Universal Time (UTC). The time maintained by both agencies should never differ by more than 0.0000001 seconds from UTC.

Re:NTP Isn't Accurate (5, Informative)

ask (1258) | more than 6 years ago | (#20524727)

Hi AC,

The NTP Pool monitors the servers and only uses those with accurate time. A server drifting several seconds off would be taken out of the pool until it got fixed.

Also, the NTP daemons are Quite Good at ignoring the servers with Bad Time Keeping.

Using ntpd with the pool servers will give you much much much more accurate time than trying to set it manually after looking at a web page.

    - ask

Re:NTP Isn't Accurate (2, Informative)

Charles Dodgeson (248492) | more than 6 years ago | (#20524729)

Please name one ntp server in the pool that it off by more than .5 seconds? The vast majority are accurate to under .1 seconds. I do not believe that the AC who said these aren't accurate understands how NTP works.

Re:NTP Isn't Accurate (3, Insightful)

Mike Morgan (9565) | more than 6 years ago | (#20525133)

3 Minutes?!?

  I have my machines synced via ntp. ntpq reports than I'm no more than 3ms out of sync with a stratum 1 time server (9ms out of sync with UNSO) and that server is synced with GPS and USNO which as you said is never more than .0001ms out of sync with UTC.

    Eye-balling like you described I can verify that I am within 2000ms of http://time.gov/ [time.gov]. I think perhaps that that website may have had issue on the date you saw it being 3 minutes different than what NTP provided.

I'd show you the ntpq output but the lameness filters prevent it.

here's a question (1)

UPZ (947916) | more than 6 years ago | (#20524643)

Is having cable modem static enough? How often does IP change from, say, Comcast?

Re:here's a question (1)

ScrewMaster (602015) | more than 6 years ago | (#20524859)

Comcast's addresses aren't static: it's all managed via DHCP. They have what they call "permanent IP addresses", which means that they won't change them very often, but they reserve the right to change them any time they want. I've had Comcast since they bought out the remains of AT&T Broadband, and they've only changed it twice (once because I upgraded to the next speed tier.)

Re:here's a question (1)

Shados (741919) | more than 6 years ago | (#20525201)

If you reread the parent a bit, they asked if it was static -ENOUGH-, not if it was static.

Re:here's a question (1)

Dun Malg (230075) | more than 6 years ago | (#20525803)

If you reread the parent a bit, they asked if it was static -ENOUGH-, not if it was static.
"static enough" is like "pregnant enough". It's either true or false, there is no matter of degree. Even if your cable IP address hasn't changed once in 7 years, it still isn't static because they can change it at will. Cable isn't static, so the answer is "no".

Dunno about Comcast - but Cox is stable (1)

NotQuiteReal (608241) | more than 6 years ago | (#20525341)

Theoretically I have a dynamic IP address. It hasn't changed in 7 years.

Re:Dunno about Comcast - but Cox is stable (1)

ask (1258) | more than 6 years ago | (#20525405)

Yeah - the criteria really for "useful for the pool" is "doesn't change more than every few years".

Re:Dunno about Comcast - but Cox is stable (1)

adolf (21054) | more than 6 years ago | (#20525553)

Every few years? Pfft.

If people are using DNS to look up NTP servers like they should be, instead of stupidly using IP addresses, then a dynamic address that changes even as often as every few days will be more than adequate.

Just get yourself a free static subdomain at a place like dyndns.org or zoneedit, and roll with it. A brief interruption due to a switch in IP addresses would likely never even be noticed by ntpd, but even if it were, there's plenty of redundancy in the NTP pool to cover the gap while the old DNS records expire before the new ones get used instead.

Of course, all bets are off if ntpd only performs one DNS lookup at startup, and then trusts the resultant IP address will be valid until the end of time, irrespective of what the domain's SOA record says should happen. If this is the case, I'd characterize it as an ntpd bug (for not following standard DNS conventions like expiration time) which should be fixed.

More NTP servers, Lower Quality? (1)

Herkum01 (592704) | more than 6 years ago | (#20524647)

I can understand the desire/need for NTP servers. The question for me becomes, does this reduce the quality of chips used in PCs? The chips that keep track of time don't have to be as accurate since, "hey, it can just sync up with NTP server." Once you let something simple like time slide, maybe they let other issues slide too because "Who is going to notice?"

Re:More NTP servers, Lower Quality? (0)

Anonymous Coward | more than 6 years ago | (#20524661)

They weren't exactly accurate before anyway.

Re:More NTP servers, Lower Quality? (1)

topham (32406) | more than 6 years ago | (#20524683)

PC Clock chips are amazingly bad and have been for 20+ years.

If they got any worse they would get the date wrong every other day.

Not so much the chips, but the timebase crystals.. (5, Informative)

Ellis D. Tripp (755736) | more than 6 years ago | (#20525151)

The component that actually determines the stability and accuracy of the real-time clock in your PC is the timebase crystal, not the RTC chip itself.

Like every other component in mass-market electronic gear, it is chosen with minimum cost as the primary consideration. Such "value engineering" also has done away with the tiny trimmer capacitor that used to be present on most motherboards, which could be used (along with a frequency counter) to tweak the oscillator frequency for better accuracy.

For real accuracy, the timebase oscillator needs to be kept at a constant temperature, which isn't possible in a PC that gets turned on and off. Ideally, the crystal (or the entire oscillator circuit) is enclosed in a package equipped with a heater element and temperature sensor, and kept at a constant temperature. Such a circuit is called an OCXO, or Oven Compensated Crystal Oscillator, and is standard equipment on laboratory grade equipment like frequency counters and signal generators.

Re:More NTP servers, Lower Quality? (0)

Anonymous Coward | more than 6 years ago | (#20524717)

> The question for me becomes, does this reduce the quality of chips used in PCs? ...
> The chips that keep track of time don't have to be as accurate since, "hey, it can just sync up with NTP server."

Timekeeping crystals, cranked out by the billion, are probably not going to get much worse than they already are. PC timekeeping is already poor, and has been for quite some time (pardon the pun).

> Once you let something simple like time slide, maybe they let other issues slide too because "Who is going to notice?"

Slippery. Other issues like what?

Re:More NTP servers, Lower Quality? (1)

PhreakOfTime (588141) | more than 6 years ago | (#20525325)

Obviously, youve not had much experience with the quality of the time function in a PC. Having an external, centralized location was the solution to deal with the already sup-par performace of local PC timekeeping.

Personally, Ive used a nice product called TrueTime WinSync [truetime.com] on my windows PC's for quite some time now, and its always the first thing I install after the yearly HD wipes.

There are many, many applications that are adversely affected when 2 PC's on a network do not have an accurate time. Some have a space of days or weeks that are acceptable, but some have a much shorter amount of allowed error between the two hosts. An example you can try anytime is to set your PC clock ahead by about 4 years and then proceed to your favorite SSL enabled website.

slashdotted.. (0)

Anonymous Coward | more than 6 years ago | (#20524651)

The load is barely noticeable...or at least until the servers get slashdotted!

Better way To Do This (4, Interesting)

nuintari (47926) | more than 6 years ago | (#20524705)

I think that a better method could be used to encourage diversity. They should take a page from the root DNS servers, or Akamai. Either use BGP anycast, which is what most of the root dns servers do now, which will probably never happen. Or, have a zone that network carriers should use on their local DNS servers, and by way of DNS lookups, encourage their customers to use. ntp.org has a default set of values for say time.overload.ntp.org that reflects the current pool. But I, as an ISP make my DNS servers directly answer queries for overload.ntp.org, and make entires such as:

time IN A 1.2.3.4
time IN A 1.2.3.5

where 1.2.3.4 and 1.2.3.5 are ntp servers on my local network. I don't allow people off my network to query my DNS servers for recursive queries, and the ntp.org DNS servers never tell anyone to use my name servers for this space anyways. This would mean that only my customers that use my DNS servers (about 99%) of them, would ever get answers for my time servers, and they would definitely be close.

And anyone whose network carrier doesn't bother to set this up, still gets generic answers from ntp.org. This works much better than just a big pool full of 1000 servers worldwide, even if you bother to use the country code dns regions, you still aren't always getting an ntp server anywhere near you.

Re:Better way To Do This (2, Informative)

ask (1258) | more than 6 years ago | (#20524761)

Hi Nuintari,

Yes - it'd be great if more ISPs offered time keeping services.

One of the plans for the pool is to let ISPs sign up their address space and tell where their NTP servers are. Then when a user using the pool asks for time servers we can point them to the local servers (if they are keeping proper time, etc etc). But it's a bit down the todo list, mostly due to lack of interests from ISPs.

  - ask

Re:Better way To Do This (2)

TooMuchToDo (882796) | more than 6 years ago | (#20525225)

Can you point me to a location to specify a Stratum 1 server? I have access to colo space as well as roof rights for a GPS antenna. I would be happy to host a Stratum 1 or Stratum 2 time server to help the NTP cause.

Re:Better way To Do This (3, Informative)

egburr (141740) | more than 6 years ago | (#20525557)

http://tf.nist.gov/service/time-servers.html [nist.gov]

All organizations interested in possibly hosting a NIST Internet Time Service server are invited to contact Time and Frequency Division Chief Thomas O'Brian for more information, including a description of the equipment that the organization must have available and a discussion of the other technical qualifications necessary to host a server: obrian@boulder.nist.gov .

Re:Better way To Do This (4, Interesting)

Charles Dodgeson (248492) | more than 6 years ago | (#20524813)

You are absolutely correct that if network carriers provided NTP services properly on their nets, then the pool wouldn't be necessary. If you go through Usenet archives you can read the history and discussion behind the creation of the pool. Everyone realizes that the pool is an inferior solution that we are stuck with because the network access service providers won't do their job.

The next time I've got a free two hours for self-torture, I'll call Verizon Business customer support and ask them about NTP service. (It will take that long to be transfered to someone who understands the question.)

Re:Better way To Do This (1)

nuintari (47926) | more than 6 years ago | (#20524947)

Oh, I understand that completely. But if the pool was a series of generic entries that individual carriers could overload in DNS if they wanted to, then all those netgear routers could default to the pool, and would take advantage of this on the networks by people who care (like me), and still have the defaults to fall back on for less helpful networks. This would allow zero configuration for the end user, unless they had a specific time server they wanted to query.

Re:Better way To Do This (2, Insightful)

adolf (21054) | more than 6 years ago | (#20525471)

Wrong solution.

Poisoning DNS is never a good idea for public (including ISP) use. Please don't suggest this.

A far better method is to use DHCP to assign one or more local NTP servers, just as is done for DNS servers and other things which may vary from network to network.

DHCP, as a protocol, supports this usage just fine. Various DHCP client implementations also support this by default[1].

All that needs to happen is for the ISP to actually run ntpd (which is trivial), and configure the DHCP server to start telling people that it exists. And then, the consumer router manufacturers, Linux distributions, and (gasp) Windows can start using it.

[1]: Unfortunately, I've had /etc/ntp.conf rewritten by a DHCP client under Linux so as to point to non-working servers, due to some machine at woh.rr.com deciding to set the NTP addresses wrong. This is obviously bad behavior, but it's just Roadrunner's fault for putting a broken configuration into production, not the client's fault for trusting and acting upon that configuration.

Re:Better way To Do This (1)

nuintari (47926) | more than 6 years ago | (#20525733)

Is it really poisoning when it is done by a bunch of networks intentionally agreeing on a set policy that is expected by the authoritative source?

Akamai does something weird that allows them to spread their subscribers' sites over a variety of networks that may or may not qualify as DNS poisoning, I suppose I could come up with something better based off their ideas. I've never looked into how the nitty gritty of their service works (we were already using it successfully when I came on board), but customers on my network going to yahoo.com will prefer the Akamai boxes on my network over the true source, or any other Akamai boxes on other networks. Which is basically what I am saying we should aim for, as opposed to the current shotgun approach.

My issues with your DHCP suggestions are twofold. For starters, not all DHCP clients honor the extra fields for ntp servers, among other things. Secondly, not everyone uses DHCP, plenty of other ways to get an IP address in this world. But everyone uses DNS.

But I do agree that we cannot just arbitrarily poison DNS. Needs some thought, but almost anything could be better than the current shotgun approach.

biznat3h (-1, Offtopic)

Anonymous Coward | more than 6 years ago | (#20524747)

The curtains flew the future o7 the 3istributions

GPS time with OpenBSD (4, Informative)

ptudor (22537) | more than 6 years ago | (#20524815)

If you grab a USB GPS receiver, I used a $60 BU-353 [google.com], you can have accurate time easily.

openbsd# dmesg | tail -3
uplcom0 at uhub0 port 2
uplcom0: Prolific Technology Inc. USB-Serial Controller, rev
1.10/3.00, addr 2
ucom0 at uplcom0
openbsd# nmeaattach cuaU0
openbsd# sysctl -a | grep hw.sensors
hw.sensors.nmea0.timedelta0=-328.10115 9 secs (GPS), OK, Tue May 15 19:48:46.898
openbsd# echo "sensor nmea0" > /etc/ntpd.conf
openbsd# echo "listen on *" >> /etc/ntpd.conf
openbsd# ntpd -ds
ntp engine ready
sensor nmea0 added
sensor nmea0: offset 328.097637
set local clock to Tue May 15 19:57:46 PDT 2007 (offset 328.097637s)
sensor nmea0: offset 0.020612
...

Re:GPS time with OpenBSD (5, Informative)

ask (1258) | more than 6 years ago | (#20524839)

Actually ... The USB latency can be pretty bad, so it's likely you'd get better time from a well-picked internet time server. You'd definitely get MUCH better time with a proper PPS (Pulse Per Second) time keeping GPS receiver or variations of that [meinberg.de].

Re:GPS time with OpenBSD (4, Informative)

mrcaseyj (902945) | more than 6 years ago | (#20525595)

In addition to the latency of USB, the nmea output of a GPS unit may not be very accurate. Go for a GPS with pulse per second if you can find one for a reasonable price. A while back I was checking the chipset specs for the cheap GPS receivers to find one with a pulse per second output. I found some but I forgot which ones they were. Of course you would have to open the case and do a little soldering. I'm not sure how you would hook it up to your server once you got the pulse per second out. I think maybe to one of the pins on the serial port that would trigger an interrupt.

Under OpenBSD I've gotten much more stable timekeeping by recompiling the generic kernel with only one simple change. I set the processor type to 586 or 686 as the case may be. Specifically in the /usr/src/sys/arch/i386/conf/GENERIC file I removed "option I486_CPU" and "option I686_CPU" so that it would be correctly configured for my pentium 166 cpu. I think the pentium has some time keeping functions the 386 and 486 didn't have. Although I haven't found the parts of the kernel code where this change does its magic.

How about semi-dynamic IPs (1)

pembo13 (770295) | more than 6 years ago | (#20524891)

If bandwidth requirements are low, I wouldn't mind joining the pool. But my ip is semi-dynamic: dynamically assigned, but rarely changes. I use DynDNS to get it.

A more practical solution... (1)

creimer (824291) | more than 6 years ago | (#20524893)

Is to have DSL/cable modems provide the NTP service since they're facing the internet anyway.

Re:A more practical solution... (1)

irving47 (73147) | more than 6 years ago | (#20524933)

hey that's what I was going to say. :)
Seriously. Put a daemon on all linksys/netgear/etc routers and have them log their own ip addresses for a while. If they stay static for a fairly lengthy amount of time, they sign into a dyndns.org-like server for a few hours a day, and become part of the pool for a while. Maybe have it dependent on their serial numbers or something.

Re:A more practical solution... (1)

Charles Dodgeson (248492) | more than 6 years ago | (#20525111)

Put a daemon on all linksys/netgear/etc routers and have them log their own ip addresses for a while
But where will all of those routers get their time from? If you've got a solution to that problem then there is no need for the pool (unless your solution is the pool).

atomic clock to PC connection? (3, Interesting)

zogger (617870) | more than 6 years ago | (#20524905)

Like a lot of guys here, we have an atomic self setting clock that works from radio broadcast. They are cheap now and work very well. What I am wondering is, do they make some sort of attachment clock, so it can set your computer's time that way? Like an atomic clock/usb cable connect thingee? Seems like if they did, we wouldn't need all these NTP servers, the government does the radio broadcasting and it is as accurate as it gets.

Re:atomic clock to PC connection? (-1)

Anonymous Coward | more than 6 years ago | (#20525015)

USB GPS receivers for the win!

Re:atomic clock to PC connection? (0, Offtopic)

J_Doh! (830090) | more than 6 years ago | (#20525607)

The Death Clock ..... just insert your finger and you will find out when you will die

Storm (1, Funny)

Anonymous Coward | more than 6 years ago | (#20524927)

Have they asked the Storm network operators? I think they could donate a few thousand machines from around the globe pretty easily.

Re:Storm (0)

Anonymous Coward | more than 6 years ago | (#20525013)

Asking them could, however, result in:
- Zero new servers
- All the existing servers going down in flames

But, well, you never know.

does this really matter? (-1, Offtopic)

Anonymous Coward | more than 6 years ago | (#20524997)

the muslims have us by the balls [wikipedia.org]
 
but still we sit here and squable over such matters? foolishness. we must start by boycotting all muslim owned businesses and countries. burn the muslim empire of lies to the ground.
 
these murdering rascals must be stopped and their liars religion must be buried by truth.

Re:does this really matter? (-1, Offtopic)

Anonymous Coward | more than 6 years ago | (#20525143)

Sounds like a really good plan. However, let's first bury the american hypocrites, terrorists and murderers.

Boycott all things amerika!

zero config and NTP? (1)

Midnight Thunder (17205) | more than 6 years ago | (#20525059)

This where a zero config version of NTP servers and client would be useful, to allow for the discovery of an NTP server on the local network, unless it already supports multicast discovery.

I am sure that there are many private networks where computers are still connecting to external time servers, when the could easily use a server on the local network.

Re:zero config and NTP? (1)

qtp (461286) | more than 6 years ago | (#20525925)

A properly configured dhcpd can specify the location of the local network's timeservers to requesting clients. The client must be configured to request (and make use of) the information as well.

how to get ntpd to stop listening on all interface (1)

ZeekWatson (188017) | more than 6 years ago | (#20525227)

Anyone know how to get ntpd to stop listening on all interfaces? I have a host with several IPs and ntpd listens on all of them ... a little bit annoying.

# netstat -l
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address Foreign Address State
udp 0 0 localhost:ntp *:*
udp 0 0 x1.example.com:ntp *:*
udp 0 0 x2.example.com:ntp *:*
udp 0 0 x3.example.com:ntp *:*
udp 0 0 x4.example.com:ntp *:*
udp 0 0 x5.example.com:ntp *:*
udp 0 0 x7.example.com:ntp *:*
udp 0 0 host.example.com:ntp *:*
udp 0 0 example.com:ntp *:*
udp 0 0 *:ntp *:*
Looks like my HTML-fu needs work too. Dunno how to stop having multiple whitespaces condensed to 1 space ... :(

Re:how to get ntpd to stop listening on all interf (0)

Anonymous Coward | more than 6 years ago | (#20525445)

Try openntpd. Its a bit more robust than the ISC daemon.

Re:how to get ntpd to stop listening on all interf (1)

gfilion (80497) | more than 6 years ago | (#20525489)

Anyone know how to get ntpd to stop listening on all interfaces?

Use OpenNTPd [openntpd.org]! No seriously, there's a bug on ntpd's bugzilla [ntp.org] asking for this that has been opened in 2003 and it's still not fixed. ntpd is so badly written that no one dares to write a patch.

And people wonder why I hate every program written by ISC...

non-root ntp server (0)

Anonymous Coward | more than 6 years ago | (#20525515)

Are there any ntp daemons that don't require root privileges? I imagine it wouldn't be to hard to maintain a delta from the system clock. If so, I wouldn't mind running something like this from a coloc.

Why not make it peer-to-peer (0, Redundant)

Pedrito (94783) | more than 6 years ago | (#20525883)

Why not design a time protocol that's peer-to-peer? Most people, like me and probably 99% of the people on the internet, can make due with time being within a few seconds (or frankly, within a couple of minutes) of accuracy, so if you only have a few nodes at the top that actually get the time from NTP and anyone who actually needs really accurate time using NTP, everyone else can share the time.

Seems to me that would get rid of the need for thousands of servers and would suit the needs of most users.
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