#36 Received truncated ancillary data
FreeBSD9f# ptpd2 -GC
(ptpd info) 00:40:43.905837 (___) Info: Going to check lock /var/run/kernel_clock
(ptpd info) 00:40:43.954284 (___) Info: No ptpd2 daemons detected in parallel (as expected)
(ptpd info) 00:40:44.001715 (___) Info: 1 ntpd daemons detected in parallel (as expected)
(ptpd info) 00:40:44.001913 (___) Info: Going to check lock /var/run/kernel_clock
(ptpd info) 00:40:44.003174 (___) Info: Startup finished sucessfully
# Timestamp, State, Clock ID, One Way Delay, Offset From Master, Slave to Master, Master to Slave, Drift, Discarded Packet Count, Last packet Received
2012-08-22 00:40:44.003564, init,
(ptpd info) 00:40:44.070203 (init) refreshed IGMP multicast memberships
(ptpd info) 00:40:44.070335 (init) now in state PTP_LISTENING
2012-08-22 00:40:44.070429, lstn_init, 1
(ptpd info) 00:40:56.005969 (lstn_init) now in state PTP_MASTER
2012-08-22 00:40:56.006281, mst, 002590fffe657726(unknown)/00
(ptpd error) 00:40:57.007770 (mst) received truncated ancillary data
(ptpd error) 00:40:58.007108 (mst) received truncated ancillary data
(ptpd error) 00:40:58.007333 (mst) received truncated ancillary data
(ptpd error) 00:40:59.006083 (mst) received truncated ancillary data
^C (ptpd notice) 00:40:59.896081 (___) shutdown on close signal
FreeBSD9#
As an aside, how about emitting the version string as part of the info logged by -C?
The box is an Intel Atom board with an Intel 82574L NIC.
Grepping through the ptpd sources yields that "truncated ancillary data" is reported if the MSG_CTRUNC flag is set in the header of a received message. This flag is defined in the standard socket.h header e.g. under Linux with the comment:
/* Control data lost before delivery. */
However, a Google search also returned this link:
http://us.generation-nt.com/answer/bug-567094-manpages-dev-recvmsg-2-doesnt-mention-msg-ctrunc-can-be-set-due-permissions-errors-help-169022341.html
which says the flag can eventually also be set due to a permission error, in the case above when SELinux denied passing of the file descriptor.
I don't know whether there's some security tool like SELinux under FreeBSD, but anyway this sounds like a possible reason for the error message.