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Why is my NTP server costing $500 per year? Part 1 (2014)

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Re: Why is my NTP server costing $500 per year? Part 1 (2014)

#101

Post by dfc »

rincebrain wrote: post #93
dfc wrote: post #63

Earlier quoted context omitted.

I have never understood why people think kod is a useful setting. Why do you think a misbehaving/improperly configured client is going to honor the kod packet? The kod packet helps with some clients but I have never seen it change the behavior of the most egregious abusers. Just ignore future requests from misbehaving clients, there is not a lot of benefit in saying "please stop misbehaving" to a client that does not…

It's not strictly harmful, I think, to presume that some percentage of misbehaving clients might just be misconfigured and honor a KoD, as long as you have other measures, unless I'm overlooking something?

I never said it was harmful.

Re: Why is my NTP server costing $500 per year? Part 1 (2014)

#102

Post by jlgaddis »

brian_cunnie wrote: post #52
fxlv wrote: post #30

I'm surprised there are no comments about the fact that these guys decided to run NTPD on a VM.

[author] NTP runs fairly decently in a VM. Don't take my word for it — look at the graphs of my servers: Here's my Google VM, notice the jitter is within +/- 5 milliseconds: http://www.pool.ntp.org/scores/104.155.144.4 Here's my Hetzner VM (Germany). +/- 10 milliseconds, though I can't help but suspect the distance from the monitoring station (Los Angeles) may have more to do with it than being a VM: http://www.pool.…

Everyone's needs differ, I suppose, so some might consider that "decent". 10ms -- or even 50ms -- might be acceptable for many (most?) use cases but not for me.

From a quick look, my own (stratum 2) server in the pool currently has an offset of just under 1/20th of one millisecond.

Regardless, thanks for contributing to the pool!

Re: Why is my NTP server costing $500 per year? Part 1 (2014)

#103

Post by jlgaddis »

Animats wrote: post #68

This is the Snapchat bug reported yesterday, right? Incidentally, how is AWS dealing with the leap second next week? Google is going to have their time servers start to run fast around 20 minutes in advance of the leap second, so they're back in sync at 00:00:60 UTC.

Nope, this is from 2014.

If memory serves, Google's "smoothing" the second out over (I think) a 24-hour period. I don't recall the exact time period off the top of my head but it's much, much longer than 20 minutes.

Re: Why is my NTP server costing $500 per year? Part 1 (2014)

#104

Post by bradfa »

brian_cunnie wrote: post #52
fxlv wrote: post #30

I'm surprised there are no comments about the fact that these guys decided to run NTPD on a VM.

[author] NTP runs fairly decently in a VM. Don't take my word for it — look at the graphs of my servers: Here's my Google VM, notice the jitter is within +/- 5 milliseconds: http://www.pool.ntp.org/scores/104.155.144.4 Here's my Hetzner VM (Germany). +/- 10 milliseconds, though I can't help but suspect the distance from the monitoring station (Los Angeles) may have more to do with it than being a VM: http://www.pool.…

For another data point, here's my Digital Ocean droplet in Bangalore which sees from 10-60k queries per second depending on the time of day: http://www.pool.ntp.org/user/bradfa

Re: Why is my NTP server costing $500 per year? Part 1 (2014)

#106

Post by late2part »

brian_cunnie wrote: post #56
late2part wrote: post #36

Earlier quoted context omitted.

t1.micro to boot - with more than the usual nondeterministic statmuxing and arbitrary "fairness" policy.

[author] Yeah, maybe that's why my AWS instance is the most jittery of my 4 timeservers (Google, Hetzner, Azure).

Your website says:

Pivotal bridges the Silicon Valley state of mind, modern approach and infrastructure with your organization’s core expertise and values. Who we are and what we do together can reshape the world

Your article suggests otherwise.

Re: Why is my NTP server costing $500 per year? Part 1 (2014)

#107

Post by detaro »

vacri wrote: post #80
detaro wrote: post #44

Earlier quoted context omitted.

Do NTP clients not retry immediately/very quickly if a request gets lost?

It's more that your device's clocks don't skew that rapidly, unless something is really wrong.

But dropping requests to reduce traffic load is counter-productive if failed requests are quickly retried.

Re: Why is my NTP server costing $500 per year? Part 1 (2014)

#108

Post by kalleboo »

DanBC wrote: post #15
Elrac wrote: post #12

Earlier quoted context omitted.

Once you put an NTP server on the 'net, it's public - pretty much like most Web sites. Sure, there are reasonable expectations of decency like for anything in the Commons, but I don't think there's any legal defense against skunks at the picnic. IIRC, the university called Netgear out for doing something stupid and disruptive, and Netgear stopped doing it. The second best possible scenario, I guess.

> Netgear stopped doing it. Netgear issued patches for the devices. Most people never update their server firmware, and we're talking about over 700,000 devices. The university still gets considerable traffic. https://en.wikipedia.org/wiki/NTP_server_misuse_and_abuse#NE...

> The university still gets considerable traffic

It'd be interested in seeing if there's been any update since 2003.

E.g., is it really "considerable traffic" by 2016 standards? The original flood in 2003 was 150 MBps - I don't think I'd notice if I got a flood of 150 MBps on my home connection.

How many of those devices are still around 13 years later?

Re: Why is my NTP server costing $500 per year? Part 1 (2014)

#109

Post by kalleboo »

njharman wrote: post #90
duaneb wrote: post #66

Earlier quoted context omitted.

Wow, I never realized operators couldn't push fixes to their routers without permission. The internet is indeed a tragedy of the commons: trivial to ruin, but a Sisyphean task to fix.

Most admins would consider having network infrastructure's firmware change outside of their control a bug/misfeature. Not to mention most devices would require reboot to apply change. And to be able to remotely change the code running a HUGE security issue.

The vast majority of admins don't even know that they're admins. They bought or received a cheap Netgear router, plugged it in, and never touched it again, except to maybe turn it off and on again when the internet was slow/down.

If you're an admin who cares about their infrastructure, you're not using a bargain-basement Netgear router, and if you are, you'll have gone through every single menu and seen the auto-update option.

Re: Why is my NTP server costing $500 per year? Part 1 (2014)

#110

Post by feld »

therein wrote: post #85
foota wrote: post #72

Earlier quoted context omitted.

Why?

Because VMs themselves might not be able to keep track of time accurately (potentially inconsistent tickrate) the way that a bare-metal setup would be able to. That's why they should be mere consumers (as in sync their time to whatever the remote says rather than contribute to the pool).

Correct, unless you have a very specific VM configuration where you are truly dedicating a CPU/core to a VM, it's not fit for being an NTP server.
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