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The NTP Pool Needs More Servers — Yours, If Available
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."
//puts on sunglasses//
Are we talking about about stratum 1 servers here?
Give me Classic Slashdot or give me death!
"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.
My AC stalker: " I personally agree with your posts most of the time, but that won't keep me from modding you troll"
http://tf.nist.gov/tf-cgi/servers.cgi
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
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
"Here Lies Philip J. Fry, named for his uncle, to carry on his spirit"
Can Google/Apple/Amazon not just throw some money at this?
It is easy and they do provide documentation. I added my server and it took about 10 minutes. Stop being a lazy shit.
Some quick searching shows one can get a USB GPS receiver for $27 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 ~$60 and an available public IP address.
My God, it's Full of Source!
OUTSIDE_IP=$(dig +short my.ip @outsideip.net)
needs the Model B, of course.
My God, it's Full of Source!
OUTSIDE_IP=$(dig +short my.ip @outsideip.net)
Perhaps you could also point out a source for a Raspberry Pi.
I once took an excursion to Reddit, and later HN. Unlimited up/down voting sucks when dealing with a hive-mind.
They can use my system if they don't mind pretty crappy latency.
Have gnu, will travel.
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.
Thank you, Edward Snowden.
"Arguments from authority are worthless." —Carl Sagan
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?
I want to delete my account but Slashdot doesn't allow it.
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...
"no to pizza"
Why would you make up an acronym for a concept that doesn't exist for words that cannot be spoken?
Boot Windows, Linux, and ESX over the network for free.
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.
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.
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).
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.
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: 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.
USB has the controller poll devices. Even on a dedicated bus there's a degree of uncertainty from the polling. Also, relying on NMEA data adds even more uncertainty, as there's no assurance that sentences are delivered in the right order or at timing more precise than one second.
My GPS triggers a serial interrupt when the PPS line goes high. The PPS line is within 1uS of UTC. After an hour or two to settle, NTP holds the time within +/-15uS.
Sure, one second precision is probably "good enough" for normal uses, but one can get more consistent time from most public servers. Providing one second precision time as a public time server is a bad idea, as NTP expects more consistent ticks and this will confuse other clients.
Running a serial GPS+NTP clock is pretty easy and provides much more stable time. Why bother with a USB GPS receiver when a more suitable serial+PPS capable one is available for only slightly more?
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.
That's not a good approach. ntpd handles a lot of edge cases - what if your drift isn't constant? what if some of your time sources turn out to be flaky? - and generally only checks the upstream clocks often enough to verify that it's still running correctly. It would be really hard to build that much functionality into a home-rolled solution, and given that it's harder to do it your way than to just run ntpd in the first place, why not?
Dewey, what part of this looks like authorities should be involved?