pool.ntp.org


pool.ntp.org: public ntp time server for everyone

Introduction

Active Servers

As of 2014-04-22

The pool.ntp.org project is a big virtual cluster of timeservers providing reliable easy to use NTP service for millions of clients.

The pool is being used by millions or tens of millions of systems around the world. It's the default "time server" for most of the major Linux distributions and many networked appliances (see information for vendors).

Because of the large number of users we are in need of more servers. If you have a server with a static IP address always available on the internet, please considering adding it to the system.

The project is maintained and developed by Ask Bjørn Hansen and a great group of contributors on the mailing lists. The code is available.

Hosting and bandwidth for the "hub" servers are currently provided by Develooper, Phyber Communications and YellowBot.

go up

News

Atom feed Subscribe in a reader

  • January 12, 2014

    Important configuration changes for NTP servers

    If you are using the standard ntpd daemon to serve time to the public internet, it’s important that you make sure it is configured to not reply to “monlist” queries. Many routers and other equipment are included in this.

    The configuration recommendations include the appropriate “restrict” lines to disallow any management queries to ntpd. Most Linux distributions will have an updated version by now that just disables the “monlist” queries, that will also solve the primary problem.

    The NTP Support wiki has more information.

    If your server is part of the NTP Pool, the system also does a periodic check if your server responds to mode6/mode7 information queries and will warn you on the manage page if it does.

    If you operate a network you can use the Open NTP Project to see if you have vulnerable devices on your network.

  • June 28, 2013

    IPv6 monitoring problems for German servers

    This week we had a period of weird behavior for the monitoring system for (mostly) German IPv6 servers.

    After much back and forth on the mailing list and numerous debugging sessions we got this information from a network engineer at Hurricane Electric:

    A bug was recently discovered in Force10 switches that cause unicast IPv6 NTP traffic to be erroneously broadcast to all ports. Due to this, there are currently access lists in place preventing some IPv6 NTP traffic from traversing the DECIX exchange, as it was causing a storm that generated nearly 1 terabit per second of traffic. This should be resolved in the near future.

    The number of IPv6 servers active in the pool appears to be about back to normal.

    Also this is the answer to "why don't we have IPv6 servers by default on all the pool zones" yet. As you might know only "2.pool.ntp.org" (and 2.debian.pool.ntp.org, etc) returns AAAA records currently.

  • May 17, 2013

    Brief outage for NTP Pool websites

    The NTP Pool "backend systems" are moving racks at Phyber. To minimize the risk of things going wrong we're doing it the old-fashioned simple way of turning everything off, moving it and turning it on again. It will mean about an hour where servers are not monitored and we can't add new ones or access the www.pool.ntp.org site.

    In the new rack there'll be more power available so when the move is done we'll have more capacity.

  • April 23, 2013

    Server upgrades at ntppool.org

    Over the last couple of months we had a couple of the "central servers" fail. It hasn't caused any service outage for the NTP clients, but some of you might have noticed that the manage NTP Pool site has been sluggish at times.

    A few months ago I bought a few new servers and sent them down to our friends at Phyber Communications who wired them up in their hosting facility. Over the last weeks I've added puppet declarations) to configure them and since earlier this evening they're in production for the web sites and a few other services.

    I have a long road map for the NTP Pool system and many of the items involve processing and storing more data to make our system better. The new servers are going to be helpful for that.

    My other project for the months have been upgrades to the GeoDNS server to support EDNS-CLIENT-SUBNET. It has been live for users of Google DNS for a while. We're still working out some kinks with the OpenDNS folks to get it fully enabled there.

  • October 9, 2012

    DNS server in Go - Big NTP Pool upgrade

    Over the last month the NTP Pool has gotten the biggest upgrade it has had in years. The changes has given us much more scalability and performance.

    As you might know, the NTP Pool system is essentially a monitoring system and a smart DNS server. Server operators register their server in the system, the monitoring system checks and evaluates the submitted servers and the DNS server gives end-users a (hopefully) local selection of servers, weighted by preferences given by the server operator and other factors.

    Last month there was a big change to the DNS server.

  • Older news...

Links

go up
Comments and questions to Ask Bjørn Hansenask@develooper.com