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The NTP Pool Needs More Servers — Yours, If Available

timothy posted about 2 years ago | from the otherwise-you'll-start-waking-up-last-week dept.

The Internet 160

Do you have a static IP or two? If so, you might be able to spread some Internet infrastructure well-being with very little effort. An anonymous reader writes "The NTP Pool project is turning 10 soon, and needs more servers to continue serving reasonably accurate time to anyone in the world."

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160 comments

I would but I just don't have the time... (5, Funny)

Anonymous Coward | about 2 years ago | (#40402091)

//puts on sunglasses//

Re:I would but I just don't have the time... (0)

Anonymous Coward | about 2 years ago | (#40402363)

//puts on sunglasses//

Yeeeeeeeaaaaaaaggghhhhhhhhh!!!!

Re:I would but I just don't have the time... (4, Funny)

Anonymous Coward | about 2 years ago | (#40402377)

That joke feels a little out of date.

Re:I would but I just don't have the time... (1)

fractalspace (1241106) | about 2 years ago | (#40403687)

"Well, Mister La Forge... It would seem that time is what we have plenty of." - Picard, Stardate 46944.2

Do you need a clock? (3, Insightful)

Hatta (162192) | about 2 years ago | (#40402255)

Are we talking about about stratum 1 servers here?

Re:Do you need a clock? (4, Informative)

GuruBuckaroo (833982) | about 2 years ago | (#40402351)

Nope. Anyone with a stable time server is encouraged to join. The operative word being "stable". It's more about providing something that will be reliably *there* when it's needed. The protocol itself will take care of accuracy.

Re:Do you need a clock? (1)

Anonymous Coward | about 2 years ago | (#40402397)

Any idea how much bandwidth this would involve?

Re:Do you need a clock? (5, Informative)

GuruBuckaroo (833982) | about 2 years ago | (#40402475)

Minimal. NTP packets are about 128 bytes. Individual clients will (if up to spec) contact no more than every 64 seconds, but up to 17 minutes once synchronized (or longer if using SNTP). I'm in the pool and I never notice the traffic.

Re:Do you need a clock? (0)

Anonymous Coward | about 2 years ago | (#40403809)

I'm in the pool and I never notice the traffic.

Then why do they need to increase the pool?

Geographic distribution (3, Informative)

tepples (727027) | about 2 years ago | (#40404013)

As I understand it, an NTP server closer to you on the Internet will provide more accurate time. Fewer hops away generally means a shorter ping and less jitter. Adding more servers in underserved countries adds more servers closer to users in those countries.

Re:Do you need a clock? (4, Informative)

mitgib (1156957) | about 2 years ago | (#40402481)

Any idea how much bandwidth this would involve?

About 1kbit on average, so nothing really. I've provided a pool server for a couple of years now, you have to run ntpd anyway, might as well join it to the pool if it is not going anywhere (IPwise) any time soon.

Re:Do you need a clock? (0)

Anonymous Coward | about 2 years ago | (#40403341)

How much memory does ntpd use?

On stable but small VPS's, memory usage is a serious concern.

Re:Do you need a clock? (2)

Matt_R (23461) | about 2 years ago | (#40403991)

virtualisation often has issues with timekeeping. I wouldn't run an NTP server on a VPS.

Re:Do you need a clock? (0)

Anonymous Coward | about 2 years ago | (#40403389)

Thanks! It looks like it MAY be possible to join as a virtual machine using kvm, which would make my vps eligible.
There is a kernel startup value of clocksource=kvm-clock
I plan to setup a graph of "ntpq -c rv" to see if it's stable or if it still fluctuates.. if anyone else has suggestions I'd love to hear them!

Re:Do you need a clock? (1)

bandy (99800) | about 2 years ago | (#40403409)

you have to run ntpd anyway

You'd be amazed at the number of machines that either aren't running it or are so mis-configured that they're not synchronized to anything.

$25 Raspberry Pi + $27 GPS reciever? (5, Interesting)

bill_mcgonigle (4333) | about 2 years ago | (#40402499)

Some quick searching shows one can get a USB GPS receiver for $27 [amazon.com] and the comments say it works with linux/gpsd, showing up as /dev/ttyUSB0.

Somebody could make a simple OS image that would narrow the scope of the problem to the availability of ~$60 and an available public IP address.

Re:$25 Raspberry Pi + $27 GPS reciever? (0)

Anonymous Coward | about 2 years ago | (#40402917)

USB won't do for NTP. You need a GPS with PPS.

Re:$25 Raspberry Pi + $27 GPS reciever? (0)

Anonymous Coward | about 2 years ago | (#40403581)

How does the PPS signal get into the PC?

Re:$25 Raspberry Pi + $27 GPS reciever? (1)

heypete (60671) | about 2 years ago | (#40403971)

Serial. USB has variable latency.

I use this receiver [amazon.com] , which is quite reasonably priced. The wiring diagram at this site [qnan.org] makes it quite easy to assemble.

Rather than driving the PPS LED directly from the PPS line, I used an NPN transistor to switch the LED on and off with each pulse. The transistor draws a negligible current from the PPS line.

I got the whole setup wired in less than an hour. Works quite well.

Re:$25 Raspberry Pi + $27 GPS reciever? (1)

bill_mcgonigle (4333) | about 2 years ago | (#40404213)

Serial. USB has variable latency.

What's the cause of the variability of the USB latency? Does it apply on a dedicated bus?

This testing [catb.org] makes it look fairly stable.

Re:$25 Raspberry Pi + $27 GPS reciever? (0)

Anonymous Coward | about 2 years ago | (#40404537)

Incorrect. pool.ntp.org isn't intended for high-precision servers. It's for "good enough" time accuracy.

USB GPS receivers work just fine for it.

Re:$25 Raspberry Pi + $27 GPS reciever? (3, Interesting)

kwark (512736) | about 2 years ago | (#40403751)

An USB GPS means no Pulse Per Second (actually 1000ms). The PPS fires an interrupt on the serial port, which should result in an interrupt every 1000ms accurate within 100us.

The lack of PPS will result in a ntpd with lots of jitter, my experience is about +/- 150ms but this depends heavily on actual USB usage and the GPS device itself. This is unsuitable for a low stratum ntpserver IMHO, so don't use it as the only timesource if you want to participate in the pool unless you advertise it as some high stratum source (I would guess 5-10).

Re:$25 Raspberry Pi + $27 GPS reciever? (1)

NevarMore (248971) | about 2 years ago | (#40403933)

So how do I get the GPS receiver to get a time signal in my basement or datacenter?

Re:Do you need a clock? (1)

Shatrat (855151) | about 2 years ago | (#40402743)

I've got three Symmetricom Stratum 0 servers, but they're only visible on our private network. :( Can't flex my geek horsepower.

What is NTP? (4, Informative)

cpu6502 (1960974) | about 2 years ago | (#40402295)

"The NTP pool is a dynamic collection of networked computers that volunteer to provide highly accurate time via the Network Time Protocol to clients worldwide." "Network Time Protocol (NTP) is a networking protocol for synchronizing the clocks of computer systems over packet-switched, variable-latency data networks. In operation since before 1985, NTP is one of the oldest Internet protocols in use." - wikipedia.

Re:What is NTP? (4, Funny)

SJHillman (1966756) | about 2 years ago | (#40402361)

What Wikipedia doesn't tell you is that Skynet had humble beginnings as a network clock...

Re:What is NTP? (1)

mitgib (1156957) | about 2 years ago | (#40402503)

What Wikipedia doesn't tell you is that Skynet had humble beginnings as a network clock...

Bow to your Cyberdyn Overlords.

Re:What is NTP? (3, Funny)

Anonymous Coward | about 2 years ago | (#40402607)

"The NTP pool is a dynamic collection of networked computers that volunteer to provide highly accurate time via the Network Time Protocol to clients worldwide." "Network Time Protocol (NTP) is a networking protocol for synchronizing the clocks of computer systems over packet-switched, variable-latency data networks. In operation since before 1985, NTP is one of the oldest Internet protocols in use." - wikipedia.

Thanks for that informative post.

Also, anyone reading Slashdot who needed such a post, your geek card has been downgraded to "minion" level. Minion level cards do not get access to the second-floor gym or the breakroom, but can still use the reference library. Take advantage of it!

Re:What is NTP? (-1)

cpu6502 (1960974) | about 2 years ago | (#40402913)

NTP could mean anything. It could be "Novell transfer protocol" or "NT processor" or "New Teacher Project" or "National Toxicology Program" or "normal temperature and pressure" or "no to pizza". By the way I work on LSEQs. As a geek card-holding person, you should know what that means. (If not turn it in.)

Okay, NOW I'm confused (3, Funny)

RulerOf (975607) | about 2 years ago | (#40403029)

"no to pizza"

Why would you make up an acronym for a concept that doesn't exist for words that cannot be spoken?

Re:What is NTP? (0)

Anonymous Coward | about 2 years ago | (#40403139)

The no to pizza Pool Needs More Servers? Are you serious?

Re:What is NTP? (3, Interesting)

Mr. Slippery (47854) | about 2 years ago | (#40403163)

NTP could mean anything. It could be "Novell transfer protocol"...

In the same sense that HTTP could be "Highly Technical TARDIS Protocol", yes. But anyone who needs HTTP expanded is a n00b (no offense, we were all n00bs once);it's a universally-used protocol.

NTP is also a universally-used protocol. Every server (every properly-managed server, at least) uses it, and many if not most PCs use it.

OTOH, the number one meaning for "LSEQ" seems to be "Leeds Sleep Evaluation Questionnaire", according to the duck. Not universal.

If you not only don't know what NTP is, but after looking it up think it's mysterious to the average /.er, you deserve a little teasing. ;-)

Re:What is NTP? (1)

tlhIngan (30335) | about 2 years ago | (#40403393)

Also, anyone reading Slashdot who needed such a post, your geek card has been downgraded to "minion" level. Minion level cards do not get access to the second-floor gym or the breakroom, but can still use the reference library. Take advantage of it!

I think it should be turned in.

The summary even stated what it was about - "providing reasonably accurate time". Sure it's not a full technical description, but it's a good quick summary of the project and what NTP is. If you want more, look it up. If not, you know it's not something you're interested in.

Better than that Opa summary.

Re:What is NTP? (-1, Troll)

cpu6502 (1960974) | about 2 years ago | (#40403527)

-1 Troll

Fcuk you all. upthe shit filled asshole you failed to wipw this morning you stupid father-fuckijng piece of shit.l. Yosutn pdi sciosutpdiocn sdocvkgh sopdcuios,jcgnlioeic eos fhsit\

Re:What is NTP? (0)

Anonymous Coward | about 2 years ago | (#40403605)

Easy on the whiskey there, buddy. It's just a stupid number from some internet dumbass.

Re:What is NTP? (2, Funny)

0racle (667029) | about 2 years ago | (#40402709)

News for Nerds. Are you so pitiful you don't know how to use a web search engine?

Oh, excuse me,

A web search engine is designed to search for information on the World Wide Web. - wikipedia

Oh damn

The World Wide Web (abbreviated as WWW or W3,[2] commonly known as the Web, or the "Information Superhighway"), is a system of interlinked hypertext documents accessed via the Internet. - wikipedia

OH GOD DAMNIT

An information system (IS)[1] - is any combination of information technology and people's activities that support operations, management and decision making. -wikipedia

You know what, look it up your damn self.

No Gov. help? (1, Interesting)

Anonymous Coward | about 2 years ago | (#40402307)

This seems like something that almost every country and government in the world, could thrown down a couple hundred dollars a year for. 3rd world, and war-torn countries need not apply for obvious reasons....

In the US, is NIST involved in this at all? If not, why not? Just seems like something that they'd be all over.

Re:No Gov. help? (3, Informative)

SJHillman (1966756) | about 2 years ago | (#40402335)

http://tf.nist.gov/tf-cgi/servers.cgi [nist.gov]

Step 1: Open Browser
Step 2: Put "nist ntp" in browser/search bar
Step 3: Click Enter
Step 4: Click on first link
Step 5: Copy link to Slashdot
Step 6: Use the remaining 8 seconds of your 10 second break to highlight what steps you took to get that link

Re:No Gov. help? (1)

GuruBuckaroo (833982) | about 2 years ago | (#40402383)

(ahem) I believe the OP was asking if the NIST time servers were part of the pool.ntp.org group. Which that page doesn't answer. So, thanks for playing, and enjoy the home version.

Re:No Gov. help? (0)

Anonymous Coward | about 2 years ago | (#40402737)

(ahem) I believe the OP was asking if the NIST time servers were part of the pool.ntp.org group. Which that page doesn't answer. So, thanks for playing, and enjoy the home version.

Only if you're dense.

Per the page, NIST operates its own NTP "pool" service, with its own load balancing scheme.

The global address time.nist.gov is resolved to all of the server addresses below in a round-robin sequence to equalize the load across all of the servers.

Getting Big ISPs involved (1)

billstewart (78916) | about 2 years ago | (#40403281)

It would make more sense for ISPs to be providing NTP service, since the shortest routes have to go through their peering points or other gateways anyway. Has the NTP Pool been trying to bring them in?

How do we help ??? (0)

Anonymous Coward | about 2 years ago | (#40402365)

They give no recommendations for how to configure your average debian or rhel server to add it to the pool. what exactly do we do ? do i need to unblock ports ? setup ntpd in a specific way ? how do i know its working ? can i use my existing tomatousb shibby mod routers which run ntpd and add them to the pool ? make it easy to join and people will join.

Re:How do we help ??? (3)

Dog-Cow (21281) | about 2 years ago | (#40402443)

It is easy and they do provide documentation. I added my server and it took about 10 minutes. Stop being a lazy shit.

Re:How do we help ??? (0)

Anonymous Coward | about 2 years ago | (#40402581)

WHERE is the documentation ? all the crap on their stuff says nothing other than set up 5 servers. what ? how ?
post notes here if you have them.
 

Re:How do we help ??? (-1)

Anonymous Coward | about 2 years ago | (#40402897)

You're too dumb to help. Let the grown-ups manage.

Seriously, if you can't find and use the same documentation that everyone else has no problem with, you should not be part of the internet infrastructure in any part, great or small. Also, if you can't do without the documentation at need, you've never learned anything about computers.

make it easy to join and you'll have a greater percentage of people fucking things up.

FTFY.

More than just a static IP (5, Informative)

MetalliQaZ (539913) | about 2 years ago | (#40402371)

Anyone considering this should carefully read the NTP pool's page on the matter. In addition to having a static IP, you need to have fairly good availability over a long period of time, and more importantly you need to be able to handle a lot of traffic. Even though the traffic is fairly low most of the time, you could experience spikes that would be difficult to handle for small businesses or amateurs. Also, anyone with metered bandwidth on their server/colo would almost certainly be unable to handle the cost.

The NTP pool is something that you have to consider carefully. You can't help out for 18 months and then decide to quit. You can expect to receive traffic for up to YEARS after you leave the pool.

-d

Re:More than just a static IP (0)

Anonymous Coward | about 2 years ago | (#40402521)

This whould be a good excuse for my isp to increase my monthly charge. Think I'll pass.

Re:More than just a static IP (2)

ShaunC (203807) | about 2 years ago | (#40402623)

Yeah, you really oughtn't try to volunteer your DSL connection. If you have a dedicated server somewhere, though, it's pretty simple to configure ntpd and register yourself as part of the pool. I've been doing my part [ntp.org] for a few years (whoops - I rebooted yesterday). The traffic really is negligible and the load is practically nil. If you've got the resources, help the cause!

Re:More than just a static IP (0)

Anonymous Coward | about 2 years ago | (#40402693)

I was in the pool around 2006-2008 on a few megabit home DSL connection. I never noticed the traffic at all, and never experienced spikes. I do remember hearing about spikes in traffic on the mailing list, but I think they were largely taken care of by that time.

So in short, I didn't experience anything like you describe. It was a painless experience.

Re:More than just a static IP (2)

kwark (512736) | about 2 years ago | (#40404025)

I've seen spikes in traffic coming from eastern european countries and Turkey a couple of years ago. Using the recent iptables module I limit traffic to ntp:
iptables -A INPUT -i eth0 -p udp --dport 123 -m recent --name ntp --set
iptables -A INPUT -m recent --name ntp --update --seconds 30 --hitcount 6 -j DROP
And the abuse eventually stopped.

Why not use EC2? (3, Interesting)

paulschreiber (113681) | about 2 years ago | (#40402389)

Can Google/Apple/Amazon not just throw some money at this?

Re:Why not use EC2? (5, Informative)

TooMuchToDo (882796) | about 2 years ago | (#40402439)

Virtual machines cannot be used for NTP:

http://support.ntp.org/bin/view/Support/KnownOsIssues#Section_9.2.2 [ntp.org] .

NTP was not designed to run inside of a virtual machine. It requires a high resolution system clock, with response times to clock interrupts that are serviced with a high level of accuracy. No known virtual machine is capable of meeting these requirements.
Run NTP on the base OS of the machine, and then have your various guest OSes take advantage of the good clock that is created on the system. Even that may not be enough, as there may be additional tools or kernel options that you need to enable so that virtual machine clients can adequately synchronize their virtual clocks to the physical system clock.

Re:Why not use EC2? (0)

Anonymous Coward | about 2 years ago | (#40402915)

Apparently Xen systems can be, though there is no mention of kvm. Additionally the article seems to be referring to the ntp client rather than the server (which probably is irrelevant... but anyway)

I wouldn't mind running a server and even purchasing more bandwidth to help out, since I don't often help out the community much, but my vps is just that, virtual.

Re:Why not use EC2? (1)

Anonymous Coward | about 2 years ago | (#40402971)

I think he means why doesn't Google or Amazon run their own NTP servers which they contribute to the pool. Google already has a public DNS system. Having a public NTP system that is part of the NTP pool would also be helpful. The network traffic would be a drop in the bucket for them. Meanwhile, they already have servers in locations that need more NTP pool support, such as South East Asia and Latin America.

Re:Why not use EC2? (2)

Kohenkatz (1166461) | about 2 years ago | (#40403189)

In theory, Microsoft runs NTP at time.windows.com. In practice, it seems very flaky. Search for it and you'll find countless forum posts about outages.

Re:Why not use EC2? (2)

Fnordulicious (85996) | about 2 years ago | (#40403851)

Can Google/Apple/Amazon not just throw some money at this?

Apple already has a few configured by default in Mac OS X: time.apple.com, time.asia.apple.com, time.euro.apple.com

$ ntpdate -q time.apple.com
server 17.151.16.23, stratum 2, offset -0.002298, delay 0.04951
server 17.171.4.13, stratum 2, offset -0.003922, delay 0.09973
server 17.171.4.14, stratum 2, offset -0.003779, delay 0.09933
server 17.171.4.15, stratum 2, offset -0.004068, delay 0.09940
server 17.171.4.21, stratum 0, offset 0.000000, delay 0.00000
server 17.171.4.22, stratum 2, offset -0.010687, delay 0.11308
server 17.171.4.23, stratum 2, offset -0.006814, delay 0.10687
server 17.171.4.24, stratum 0, offset 0.000000, delay 0.00000
server 17.151.16.12, stratum 2, offset -0.002686, delay 0.04926
server 17.151.16.14, stratum 2, offset -0.002507, delay 0.04927
server 17.151.16.20, stratum 2, offset -0.002333, delay 0.04941
server 17.151.16.21, stratum 2, offset -0.002317, delay 0.04892
server 17.151.16.22, stratum 2, offset -0.002512, delay 0.04955
server 17.151.16.38, stratum 2, offset -0.002454, delay 0.04890

$ ntpdate -q time.asia.apple.com
server 17.82.253.7, stratum 2, offset 0.003790, delay 0.25430
server 17.83.253.7, stratum 2, offset -0.000764, delay 0.15932

$ ntpdate -q time.euro.apple.com
server 17.72.255.12, stratum 2, offset -0.006641, delay 0.20169
server 17.72.255.11, stratum 2, offset -0.006988, delay 0.20267

So it looks like they’ve got a reasonable handful in the pool. Dunno about Google or Amazon because googling didn’t turn up anything immediately obvious.

In the mean time.... (1)

Xtifr (1323) | about 2 years ago | (#40402513)

I've always wondered about the defaults to have every RH/Debian/Suse/Ubuntu/etc. box talk directly to the pool. I know that for years, the pool has been considered fully sufficient to meet these needs, but it just always struck me as more efficient for an organization to run its own NTP server--one machine talking to the pool--and have other machines in the organization talk to that, rather than having all the machines in the organization talk to the pool.

For home use, I actually use ntpupdate in a once-a-day cron job, rather than having a full ntpd talking to the pool all day long. It was a little more work to set up (which is also something I wish could be addressed), but combined with automatic drift correction, it seems more than adequate for my needs.

Not that I want to discourage people from contributing to the pool! That's a great idea. I just think it might also be beneficial if people learned to be less abusive of the pool, and if distro makers made it easier to not abuse the pool.

Re:In the mean time.... (4, Informative)

fuzzyfuzzyfungus (1223518) | about 2 years ago | (#40402717)

The 'default' is what it is because it is the setting that provides the best chance of working right out of the box. Hitting a known public NTP source qualifies as a pretty sane default.

Now, if you are going to be running a bunch of systems, it certainly is polite, as well as efficient, to run your own NTP server for your internal systems, just as you likely run your own DNS server for them. However, that isn't really something you can sensibly set as the default; because every organization's internal server will have a different address and smaller sites/single users/laptops frequently off the LAN simply won't have one.

Not all that dissimilar from the fact that most distro's package managers default to pointing directly to the public package mirrors. That is obviously nuts from the perspective of anybody running more than a few machines, you'll waste enormous amounts of time and bandwidth if you aren't caching packages and updates; but your default can't really assume the existence of a local cache...

Re:In the mean time.... (1)

Xtifr (1323) | about 2 years ago | (#40402877)

Yeah, I kinda get that. Still, it seems like it's harder than it ought to be to use something other than the default. When I set up a system, it generally asks me what I want to use for DNS, but never asks what I want to use for NTP.

Package pools, I think, are slightly different, since they're distro-specific and take a lot of space, and even a moderate-sized organization may be unwilling to host their own mirrors for all the distros they use internally. Still, I certainly wouldn't object to the distros making it little easier to do so for companies that want to.

Re:In the mean time.... (1)

csnydermvpsoft (596111) | about 2 years ago | (#40403327)

Many/most distros will use the NTP servers provided via DHCP (if configured) instead of the built-in defaults. I know this is true for Ubuntu, at least — not sure if their dhclient/ntpd configuration is nonstandard or not (knowing Ubuntu, there's a high likelihood that it is).

Re:In the mean time.... (3, Interesting)

heypete (60671) | about 2 years ago | (#40404105)

I've always wondered about the defaults to have every RH/Debian/Suse/Ubuntu/etc. box talk directly to the pool. I know that for years, the pool has been considered fully sufficient to meet these needs, but it just always struck me as more efficient for an organization to run its own NTP server--one machine talking to the pool--and have other machines in the organization talk to that, rather than having all the machines in the organization talk to the pool.

They actually talk to a "vendor" subdomain of the pool [ntp.org] : 0.rhel.pool.ntp.org, 1.rhel.pool.ntp.org, 2.rhel.pool.ntp.org, etc.

They provide vendor-specific subdomains and encourage vendors to provide NTP servers to the pool. Thus, if there's some abuse or misconfiguration that results in excessive traffic they can change the vendor-specific subdomain to prevent that traffic from flooding NTP servers without inconveniencing clients that use the general pool.

Anyway, yes: it's better for an organization to have one or two local time servers communicate with the pool (or other sources of time) and then provide time service to the local network. Still, talking to the pool is a reasonably sane "general purpose" default.

microsoft and nist (0)

Anonymous Coward | about 2 years ago | (#40402557)

why aren't time.windows.com and time.nist.gov in the pool?

Woo-hoo! First post! (4, Funny)

PPH (736903) | about 2 years ago | (#40402627)

They can use my system if they don't mind pretty crappy latency.

Re:Woo-hoo! First post! (1)

Just Some Guy (3352) | about 2 years ago | (#40403191)

They don't, as long as it's consistently crappy. If tests can establish that you always have a delay of 1000.000ms, your machine is a better time source than another that has 100 += 99 ms.

US Navy Master Clock (2, Informative)

cffrost (885375) | about 2 years ago | (#40402651)

These three are the US master clock's stratum-1 servers. They most likely will not run out of bandwidth. The last one isn't (intended) for civilian users, so don't come to me if an aircraft carrier, F/A-18 Hornet, etc. smashes through your front door.

tick.usno.navy.mil
tock.usno.navy.mil
ntp.usno.navy.mil

More information. [navy.mil]

Re:US Navy Master Clock (5, Insightful)

Just Some Guy (3352) | about 2 years ago | (#40403205)

These three are the US master clock's stratum-1 servers. They most likely will not run out of bandwidth.

Don't do that, though; it's anti-social. The NTP ecosystem is much better off scaling horizontally than vertically.

Re:US Navy Master Clock (0)

Anonymous Coward | about 2 years ago | (#40404065)

I'm running a group of stratum 2's off of tick & tock (alongside a couple of others), but then that is in a datacenter with a couple of thousand servers in it.

Re:US Navy Master Clock (2)

Just Some Guy (3352) | about 2 years ago | (#40404493)

That is a perfectly reasonable use. Basically, you're configuring a few internal machines to serve as proxies for the rest. And from an operations standpoint, you're providing a (likely) much more stable clock source that's not at the whims of your upstream network.

No data behind the claim (2)

Gothmolly (148874) | about 2 years ago | (#40402675)

Without metrics, this is just "Please sir, may I have some more?"
How about telling us how many servers are there, what their utilization is, client load, etc?

Re:No data behind the claim (1)

negge (1392513) | about 2 years ago | (#40403937)

You took the time to post here but didn't take the time to RTFA, which by the way would have provided answers to all your questions?

How about static DNS name vs static IP address? (0)

Anonymous Coward | about 2 years ago | (#40402807)

If the NTP Pool folks would allow us to specify a DNS name rather than an IP address I would host a server. My DNS name doesn't change because I use a dynamic DNS service. My IP address changes every time the cows lean against the barbed wire that the phone company uses to provision my DSL circuit. (Amazingly enough, I get 10.2 Mbps speed when the cows are not nearby.)

Re:How about static DNS name vs static IP address? (1)

Anonymous Coward | about 2 years ago | (#40403303)

Because their load balancing shouldn't have to resolve your IP every time they send someone to your server. Tends to fuck up the accuracy of the, you know, time... Also, your connection is not reliable enough based on your comment. This is not folding at home, SETI at home, etc. They don't want people like you fucking things up.

Re:How about static DNS name vs static IP address? (2)

profplump (309017) | about 2 years ago | (#40403453)

The NTP protocol doesn't support changing IPs -- there's a long-term relationship among hosts in an NTP group. Servers like yours that hop on and off the network are only useful for single-sync applications and therefore are not suitable for inclusion in an NTP pool.

Re:How about static DNS name vs static IP address? (1)

PhotoJim (813785) | about 2 years ago | (#40403585)

Many ISPs will give you a static IP for a reasonable monthly charge.

Some do it by default, like mine.

Don't volunteer on broadband... (1)

jg (16880) | about 2 years ago | (#40403565)

Since all broadband connections have bufferbloat (to some degree or other), in all technologies (fiber, DSL and cable alike), it isn't a good idea to volunteer to run an NTP server on such a connection, even if it is/has been reliable. Bufferbloat will induce transient bad timing into your time service; even more fun, in often a asymmetric way, pretty much any time you do anything over that link.
                                                                    - Jim

Re:Don't volunteer on broadband... (1)

profplump (309017) | about 2 years ago | (#40403995)

While high-precision public servers are nice, most applications for NTP aren't sensitive to the amount of jitter introduced by consumer-grade endpoint (which I'd characterize as almost never exceeding 100ms, and often below 50ms). If you have an application where that much jitter in your NTP sync is an issue you need a local NTP server anyway, and quite possibly a local time source.

Too many idiots are pissing in the pool. (4, Interesting)

jcochran (309950) | about 2 years ago | (#40403619)

I used to have a computer in the pool, but removed it due to disgust with the NTP abusers out there. When I looked at the logs, I would see that the vast majority of incoming traffic was from a relatively small handful of IP address. For normal well behaved users, you would see them hit you every 64 seconds and over a period of a few hours slowly back off until they do a query only once every 1024 seconds. Reasonable and well behaved. Even a relatively low bandwidth DSL line could handle a lot of users like that.

Unfortunately, not all the users are reasonable and well behaved. There were a few addresses that were hitting me with a query per second. And you can't blacklist these anti-social idiots because if you do, they're still consuming inbound bandwidth. After a period of time where 1% of the users were consuming 99% of my donated resources, I left the pool out of disgust. Was still getting hits from the idiot users a year later.

To make their idiocy even more evident, the SHORTEST interval that NTPD will hit a server is once per 16 seconds. So those once a second idiots were using software that itself was written by idiots.

Would I donate to the pool again? Nope. Not at long as there are invalid NTP clients that hit that often. If I could be assured that the idiots are gone, then I'd donate. Until then, I don't need the headaches.

Re:Too many idiots are pissing in the pool. (1)

primus1024 (805561) | about 2 years ago | (#40404001)

Could that be a bunch of computers behind NAT using the same external IP or you think those users were genuinely malicious?

Re:Too many idiots are pissing in the pool. (1)

profplump (309017) | about 2 years ago | (#40404119)

Probably not malicious -- probably just using bad software, or putting in ridiculous settings because they don't understand how NTP works.

Re:Too many idiots are pissing in the pool. (4, Interesting)

profplump (309017) | about 2 years ago | (#40404069)

I've got one better -- I actually had a pool user call my ISP and get me disconnected (temporarily) because I was "hacking" them on UDP port 123.

Re:Too many idiots are pissing in the pool. (1)

sys_mast (452486) | about 2 years ago | (#40404099)

Any chance it could have been valid clients, but through NAT looks like one client with an excessive amount of hits/min? Of course a reasonable person should have one NTP client hit the pool, and sync all the rest of the clients to the local. I guess i'd be surprised if it was a poorly coded client, does anyone use anything besides the default NTPD?

Re:Too many idiots are pissing in the pool. (1)

Meostro (788797) | about 2 years ago | (#40404103)

To make their idiocy even more evident, the SHORTEST interval that NTPD will hit a server is once per 16 seconds. So those once a second idiots were using software that itself was written by idiots.

So you don't think this was 1 NATted IP running 16+ servers behind it? As someone said above [slashdot.org] the default for some OSes is to hit the pool directly.

Guess What? (0)

Anonymous Coward | about 2 years ago | (#40403771)

Stop requiring static IPs. NTPd.conf takes host names, you know? There's no reason to require a static IP, but that keeps me and my ACTS-disciplined oscillator off the list.

Re:Guess What? (1)

profplump (309017) | about 2 years ago | (#40403935)

NTP requires long-term relationships among the hosts in the peer/server group. As implemented that means static IPs, but even if you changed the system to do repeated DNS lookups the NTP pool couldn't use hostnames -- the DNS-based pooling currently in use does not include any mechanism to distribute hostnames, nor do most NTP clients provide any method to easily consume such data even if it were available.

I did run one (0)

Anonymous Coward | about 2 years ago | (#40403873)

I have a mess of static IPs on a dedicated server and did run a public stratum 2 NTP server for quite a while. People were using it (rather than pool) and got annoyed with me when I changed IPs and stuff, updating DNS of course. That made me think twice about continuing. When I virtualized all the infrastructure, I discontinued the server, since an ntp server running in a vm is just about pointless. I expect I'm not the only person retiring an NTP server for this reason, as I move to "the cloud".

NTP server VM image, or minimal NTP server config (0)

NevarMore (248971) | about 2 years ago | (#40403997)

Is anyone publishing a minimal NTP server VM image?

What would be required for a bare bones NTP server? It seems like a light weight, low-impact service
  - A device that runs linux
  - A device that has a wired network port
  - A device that has a USB and serial port (for integrating with hardware clocks/GPS)
  - Low power (possibly PoE)

We're talking on the order of MB of storage and memory. Something that can be plugged in near a window and forgotten for years.

NTP Pool = Socialism (1)

Anonymous Coward | about 2 years ago | (#40404035)

Real Americans pay for the time and don't rely on handouts.

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