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Comment by jbeda | Hacker News Reader

As part of Google Compute Engine we provide an NTP server to the guest which is based on Google Production time. As such our VMs get to take advantage of this leap second smearing implementation. I was going to mention this at my talk at IO but forgot.

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So a VM on G's Compute Engine could in turn run an NTP server that exported G's Production Time? Do I also see GPT on App Engine?

Any chance Google could just make a GPT NTP server available as a public service anyway, just as 8.8.8.8 is their public ping responder. ;-)

8.8.8.8 and 8.8.4.4 are Google Public DNS, not a "ping responder." https://developers.google.com/speed/public-dns/

Google does provide time servers, although I'm not sure whether they are officially supported. The addresses are:

    time1.google.com
    time2.google.com
    time3.google.com
    time4.google.com

Yeah, sorry, I know they're the public DNS, but they're also jolly handy as unforgettable IP addresses you expect to be able to ping, hence the smiley.

Good news about the time{1..4} NTP servers, I'll give them a try, thanks.

I don't know about GAE specifically but I'd be very surprised if it didn't see the same time as the rest of Google. They would have had to do work to make that happen.

Marco's blog post (linked) had a similar idea - running ntp with -x for a day so it smears time.

In case anyone is looking for the actual link to marco's posts on ntp:

http://my.opera.com/marcomarongiu/blog/index.dml/tag/ntp

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