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."

What is NTP?

[cpu6502]

"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:No Gov. help?

[SJHillman]

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:Do you need a clock?

[GuruBuckaroo]

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.

More than just a static IP

[MetalliQaZ]

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:Why not use EC2?

[TooMuchToDo]

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:Do you need a clock?

[GuruBuckaroo]

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?

[mitgib]

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.

US Navy Master Clock

[cffrost]

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:In the mean time....

[fuzzyfuzzyfungus]

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...

Geographic distribution

[tepples]

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.