Joining NTP pool

I saw a slashdot article ( and now I'm thinking of adding my linode to the ntp pool. I'm not yet running any ntp software on my linode, yet my linode's clock already appears to be very well synced up with ntp sources. So I'm guessing that the UML host is already sync'ed up via ntp, and this synchronization somehow trickles down to my individual host.

Which leads me to my question. Would it be a waste of time (haw) to join the ntp pool if the UML host is already tweaking my clock? It might in fact be a bad idea to join the ntp pool since ntpd is probably assuming that no other agency is adjusting the system clock.

4 Replies

The linode server is time sync'd and, by default, your own linode will follow the server clock so there is no need to run ntp on your linode.

I think the question here is whether or not he should run an ntp server, so that other people can grab ntp data from him.

I would personally suggest that this wouldn't be a good idea. Since it's synced up already by the host, you don't know what it's synced to, so you can't yourself vouch for the accuracy of that source. Furthermore, you don't know how many hops you are from a known good time source, although you could always ask, I guess. :)

Well i added my two servers to the pool yesterday..

They do checking to see how out of date ur server is etc so.. if your host was out i assume you would find out pretty quickly..

I agree with Ciaran, the fact that you don't have a solid reference for your NTP server makes it a bad choice to add to the ntp pool project.

Think about it:

  • at what stratum are you running?

  • what are you presenting as an upstream reference?

The whole idea behind NTP is that you have a traceable upstream source and the ntp client can make informed decisions about accuracy. With a linode you're dependant on the host's clock and you have no idea if it's synched, or to what stratum is synched. In exactly the same way, the client also cannot root out "bad tickers".



Please enter an answer

You can mention users to notify them: @username

You can use Markdown to format your question. For more examples see the Markdown Cheatsheet.

> I’m a blockquote.

I’m a blockquote.

[I'm a link] (

I'm a link

**I am bold** I am bold

*I am italicized* I am italicized

Community Code of Conduct