NTP users are strongly urged to take immediate action to ensure that their NTP daemons are not susceptible to being used in distributed denial-of-service (DDoS) attacks. Please also take this opportunity to defeat denial-of-service attacks by implementing Ingress and Egress filtering through BCP38. See ConfiguringParseRefclocksDev for discussion of this topic.
ntp-4.2.8p15 was released on 23 June 2020. It addresses 1 medium-severity security issue in ntpd, and provides 13 non-security bugfixes over 4.2.8p13.
Are you using Autokey in production? If so, please contact Harlan - he's got some questions for you.
6.1.13. Configuring Parse Refclocks
Configuring a Meinberg GPS167BGT
Harlan uses the Yost serial connector scheme
ports get Yost DCE adapters on them. Note that the
ports do not provide PPS, while the
ports provide PPS on pin 1.
I used modes 7/135 for these ports.
Configuring a Meinberg DCF77-C51
The C51 is connected via a modem cable (straight serial cable).
Harlan used a Yost DTE adapter.
server 127.127.8.0 mode 2
fudge 127.127.8.0 time1 <delay at your place>
The time1 value defaults to 10.
There is also a RAWDCF cable, which would apparently use mode 14 or 16.