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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//
"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"
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.
Poor means hoping the toothache goes away.
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"
Virtual machines cannot be used for NTP:
http://support.ntp.org/bin/view/Support/KnownOsIssues#Section_9.2.2.
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.
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.
Poor means hoping the toothache goes away.
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.
Being a spelling & grammar Nazi is a sign you do not poses the intelligence to contribute to the conversation
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)
They can use my system if they don't mind pretty crappy latency.
Have gnu, will travel.
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...
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.
Dewey, what part of this looks like authorities should be involved?
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.
Until somebody hard codes your server into their commercial firmware and screws up the NTP implementation.
http://pages.cs.wisc.edu/~plonka/netgear-sntp/