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Running PTP Receiver on FreeBSD

A while back I installed a GPS-disciplined PTP time server at home. This was partially due to a contract project that was using PTP (but totally did not require having such a dedicated time server), but mostly just because I am interested in time. On most of my hard-wired machines I already have them set up to use PTP as their time source (everything else will be using the NTP server on this time server). I recently installed FreeBSD on an old server (and on some workstations), but never got around to setting up PTP on it. I saw almost no mention of using PTP on FreeBSD on the internet, so I decided I would do a write-up on how I got ptpd2 working as a receiver/client/slave (which besides the installation, turned out to be very straightforward).

Installing ptpd2 via ports

ptpd2 is not available as a binary package at the time of writing, so it needs to be installed via ports. I have been solely using pkg for installing packages, so I first needed to get set up to build ports. This is mostly based on the FreeBSD Documentation on setting up and using poudriere.

NOTE: This is not necessarily following “best practices” for dealing with ports on a system that primarily uses binary packages. This is just how I managed to get it to work. I would recommend reading the official documentation if you plan to follow this.

Install poudriere:

pkg install poudriere

The config for poudriere is located at /usr/local/etc/poudriere.conf. I already use ZFS, so I decided to enable its use in poudriere by uncommenting this line:

ZPOOL=zroot

I didn’t want to bother looking for other mirrors, so I also used the suggested one:

FREEBSD_HOST=https://download.FreeBSD.org

I left the rest of the config as-is.

Create jail for poudriere to use (replace release version with whatever you are running):

poudriere jail -c -j pjail-amd64-15_0 -v 15.0-RELEASE

Pull ports (if not using latest, you may prefer to use one of the quarterly branches instead):

poudriere ports -c -m git+https

I ran the following to see what options were available for ptpd2:

poudriere options -j pjail-amd64-15_0 -c net/ptpd2

I disabled SNMP, as I was not planning on using SNMP to monitor it. I also disabled DOCS for all the build dependencies, since I would not be installing those packages on the host anyway.

I then created a file named portlist-ptp (the name doesn’t really matter) that contained the port I wanted to build:

net/ptpd2

Then used poudriere to build the ports in that file:

mkdir /usr/ports/distfiles
poudriere bulk -j pjail-amd64-15_0 -f portlist-ptp

I tried to use poudriere’s support for downloading binary packages when it could, but after working around some bugs, it would refuse to use pkg even if I used the right repo such that the version matched. This might be fixed in the next release. Or I might have just been doing something dumb. Not a big deal as this package only had 9 dependencies for the build, but it would have sped up the build process.

After building, the resultant package is in /usr/local/poudriere/data/packages/pjail-amd64-15_0-default/All/, and can be installed using:

pkg add /usr/local/poudriere/data/packages/pjail-amd64-15_0-default/All/ptpd2-2.3.1_2.pkg

Setting up ptpd2

The service installed by ptpd2 expects the config to be located at /usr/local/etc/ptpd2/ptpd2.conf, or specified by ptpd2_configfile in rc.conf. I used the client-e2e-socket.conf.sample file as a base, modifying the following options:

  • ptpengine:interface: Changed to the proper interface on my machine (ql0)
  • ptpengine:ip_mode: Changed to hybrid
  • Replaced instances of /usr/scratch/log with /var/log
  • global:quality_file_max_size: Set to 1024 (1 MiB)
  • global:quality_file_truncate: Set to Y
  • global:status_update_interval: Increased to 30 seconds
  • global:log_file_max_size: Set to 16384 (16 MiB)
  • global:log_file_truncate: Set to Y
  • global:statistics_log_interval: Increased to 30 seconds
  • global:statistics_file_max_size: Set to 16384 (16 MiB)
  • global:statistics_file_truncate: Set to Y

I then disabled ntpd and enabled ptpd2:

service ntpd stop
service ntpd disable
service ptpd2 enable
service ptpd2 start

After that, it just worked. From /var/log/ptpd2.status.log:

Host info          :  shulgin, PID 97033
Local time         :  Fri Feb 13 18:31:17 CST 2026
Kernel time        :  Sat Feb 14 00:31:17 UTC 2026
Interface          :  ql0
Preset             :  slaveonly
Transport          :  ipv4, multicast
Delay mechanism    :  E2E
Sync mode          :  ONE_STEP
PTP domain         :  0
Port state         :  PTP_SLAVE
Local port ID      :  a0481cfffee079a8(unknown)/1
Best master ID     :  3ce4b0fffec7abc2(unknown)/1
Best master IP     :  10.0.0.20
GM priority        :  Priority1 1, Priority2 1, clockClass 6
Time properties    :  PTP timescale, tracbl: time Y, freq Y, src: GPS(0x20)
UTC properties     :  UTC valid: Y, UTC offset: 37
Offset from Master : -0.000002921 s, mean -0.000000883 s, dev  0.000006787 s
Mean Path Delay    :  0.000067972 s, mean  0.000066930 s, dev  0.000000202 s
Clock status       :  in control
Clock correction   : -0.849 ppm, mean -0.835 ppm, dev  0.006 ppm
Message rates      :  2/s sync, 2/s delay, 1/2s announce
TimingService      :  current PTP0, best PTP0, pref PTP0
TimingServices     :  total 1, avail 1, oper 1, idle 0, in_ctrl 1
Performance        :  Message RX 25/s, TX 1/s
Announce received  :  105
Sync received      :  417
DelayReq sent      :  425
DelayResp received :  425
State transitions  :  3
PTP Engine resets  :  1

Tracking PTP statistics with Telegraf

I use Telegraf and InfluxDB to monitor my servers, and already have my Linux machines reporting PTP statistics in. The statistics gathered make ptpd2 somewhat incompatible with those from ptp4l, so I’ll need to create new visualizations in Grafana, but not a big deal.

/var/log/ptpd.log contains the statistics I am after. The first line of the file is a header for the CSV-formatted data that follows, so we know the fields:

# Timestamp, State, Clock ID, One Way Delay, Offset From Master, Slave to Master, Master to Slave, Observed Drift, Last packet Received, Sequence ID, One Way Delay Mean, One Way Delay Std Dev, Offset From Master Mean, Offset From Master Std Dev, Observed Drift Mean, Observed Drift Std Dev, raw delayMS, raw delaySM
2026-02-13 18:27:47.299886, init, 
2026-02-13 18:27:47.400574, lstn_init,  1 
2026-02-13 18:27:49.355197, slv, 3ce4b0fffec7abc2(unknown)/1,  0.000000000,  0.000000000,  0.000000000,  0.000000000, -79.605102539, I, 03911, 0.000000000, 0, 0.000000000, 0, 0, 0,  0.000000000,  0.000000000
...
2026-02-13 19:22:50.238305, slv, 3ce4b0fffec7abc2(unknown)/1,  0.000072714,  0.000008748,  0.000071833,  0.000092066, -953.521102539, D, 06565, 0.000072590, 62, 0.000000301, 4067, -959, 2,  0.000092066,  0.000075741

I’m not going to go into detail about the config, but in the end this is what I ended up with for the Telegraf input config:

# PTP statistics
[[inputs.tail]]
  name_override = "ptpd2"

  files = ["/var/log/ptpd.log"]

  data_format = "csv"

  csv_trim_space = true

  csv_column_names = ["time",   "state",  "clock_id", "ign_0", "off",   "ign_1", "ign_2", "drift", "ign_3",  "ign_4", "owd_mean", "owd_stddev", "off_mean", "off_stddev", "drift_mean", "drift_stddev", "ign_5", "ign_6"]
  csv_column_types = ["string", "string", "string",   "float", "float", "float", "float", "float", "string", "int",   "float",    "int",        "float",    "int",        "int",        "int",          "float", "float"]

  fieldexclude = ["time", "state", "clock_id", "ign_*"]

I could have probably gotten Telegraf to parse the time column as well, but I’m fine with it just treating it as the current time of the machine, so I didn’t bother.