Raspberry Pi 2 – NTP server | Stratum 1

Well, it’s done! I have a small RP2 acting as a Stratum 1 NTP Server using a GPS module with the GPIO input.

It’s been added the canadian pool.ntp.org cluster of NTP servers and has begun answering queries. The process was relatively simple with a few things to keep in mind :

  • The default repository do not hold a recent image of the NTPD image. You are better off downloading and compiling the archive yourselves.
  • Here is the GPS module for the Raspberry Pi A+/B+/2 : Link
  • If you have an older Raspberry Pi : Link
  • You might need an antenna to lock on to the GPS signal. Especially true if you are indoors. Depending if a GPS repeater is present, it might be impossible to get a lock anywhere else than the top floor of a building or a room with windows.
  • I made the mistake of ordering the old style of GPS module for the RP2. It does fit, but it’s a bit awkward and I need to get a GPIO riser so that the antenna isn’t hitting the USB/Ethernet connectors. For now, the GPS module is just not fully connected to the GPIO board. There might be 3 centimeters of the connectors exposed. Everything seems to be working fine but doesn’t look very clean.

Here is a small taste of what kind of devices seem to be hitting my server :

tcpdump_ntp

 

stjhnbsu1kw-047055188012.dhcp-dynamic.FibreOp.nb.bellaliant.net
hlfxns016cw-156057136226.dhcp-dynamic.FibreOp.ns.bellaliant.net
216-211-57-239.dynamic.tbaytel.net
hlfxns016cw-156057150054.dhcp-dynamic.FibreOp.ns.bellaliant.net
hlfxns0187w-047055119103.dhcp-dynamic.FibreOp.ns.bellaliant.net
hlfxns0187w-142177064089.pppoe-dynamic.High-Speed.ns.bellaliant.net
stjhnbsu1kw-047054246090.dhcp-dynamic.FibreOP.nb.bellaliant.net
hlfxns0188w-099192087052.pppoe-dynamic.High-Speed.ns.bellaliant.net
dsl.198.58.171.47.ebox.ca
stjhnbsu0ww-142134156121.dhcp-dynamic.FibreOP.nb.bellaliant.net
192-0-170-198.cpe.teksavvy.com
216-211-115-4.dynamic.tbaytel.net
hlfxns0187w-047055097081.dhcp-dynamic.FibreOp.ns.bellaliant.net
fctnnbsc38w-207179184024.dhcp-dynamic.FibreOp.nb.bellaliant.net
hlfxns0169w-142068218193.pppoe-dynamic.High-Speed.ns.bellaliant.net
stjhnbsu1kw-047055177028.dhcp-dynamic.FibreOp.nb.bellaliant.net
24.114.221.2
S010674d02b6711ee.ca.shawcable.net
216-211-71-83.dynamic.tbaytel.net
hlfxns0187w-047055122041.dhcp-dynamic.FibreOp.ns.bellaliant.net
stjhnbsu1kw-099192014064.dhcp-dynamic.FibreOp.nb.bellaliant.net
stjhnbsu0nw-156034190005.dhcp-dynamic.FibreOp.nb.bellaliant.net
stjhnbsu1kw-047055179184.dhcp-dynamic.FibreOp.nb.bellaliant.net
HLFXNS016CW-142134092016.dhcp-dynamic.FibreOp.ns.bellaliant.net
stjhnbsu0ww-142134158198.dhcp-dynamic.FibreOP.nb.bellaliant.net
184.66.68.82
hlfxns0163w-142068001198.dhcp-dynamic.FibreOp.ns.bellaliant.net
stjhnbsu0ww-142134152181.dhcp-dynamic.FibreOP.nb.bellaliant.net
hlfxns016cw-156034028230.dhcp-dynamic.FibreOP.ns.bellaliant.net
dsl.198.58.150.186.ebox.ca
stjhnbsu0ww-047054187034.dhcp-dynamic.FibreOP.nb.bellaliant.net
173.239.175.242
stjhnbsu1kw-047054018211.dhcp-dynamic.FibreOP.nb.bellaliant.net
stjhnbsu1kw-047055183093.dhcp-dynamic.FibreOp.nb.bellaliant.net
stjhnbsu1kw-047054018159.dhcp-dynamic.FibreOP.nb.bellaliant.net
199.168.250.156 (ip-199.168.250.156.reverse.skycomp.ca)
216-211-95-251.dynamic.tbaytel.net
216-211-44-86.dynamic.tbaytel.net

That’s a lot of cable modem/CPE devices. I wonder why ISP are not using internal servers. Seems like time is something you would want full control over.

 

One thought on “Raspberry Pi 2 – NTP server | Stratum 1

  1. Pircs says:

    Hi. I found your site because my ntp server has selected your time source as system peer. It’s Saturday and I just wanted to see where my time was coming from.

    Thanks!

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