What time is it Mister Fox?
In some vague sense, I have been trying to build my datacenter with the principles over at Infrastructures.org. One of the principles is Time Synchronization.
I considered buying a network time device that uses GPS to provide a local stratum 1 server -gizmos such as Symmetricom or Spectracom product line.
After looking at their sites as well as several others and only finding links for ‘request quote’ for pricing, I decided to look for alternatives. I’m obsessive, but not so obsessive that I feel like getting marketing spam just for looking at gear.
University of Utah IT Department did a good writeup of their NTP architecture and how they intend to distribute time across campus.
A little too big an architecture for me – I just want to set the time on a few dozen servers and clients without having each of them go out to the net.
So, with a dedicated device purchase on hold because of arcane marketing practices, I happened to be setting up BGP on my router with the help of my friend Brian who runs Secure Network Designs. He set up a large-ish ISP called Airnetlink, which was doing wireless T1 sales in office parks. Since he had multiple T3s that were multi-homed (and he’s an old friend) he was able to quickly set me up on the BGP side, and I noticed in the Cisco config script the following:
ntp clock-period 17180547
ntp master 6
ntp server 192.5.41.41
So, I did a little digging, and discovered that my router can poll data from the US Naval Observatory (most people’s choice for an NTP server) – there are two, tick and tock. Also, the router can do NTP broadcast into my network, which eliminates the need for each machine to poll.
So I will just be setting the cisco to broadcast ntp into my interior and configure NTPD to listen in broadcast mode.