[ntp:questions] HopfClockSerial with Suse 10.2

Gerhard Pisl gerhard at pisl.de
Sat Feb 17 19:17:33 UTC 2007

I currently try to get a HopfClock Serial 6020 to run with NTP under Linux
SuSE 10.2.

This configuration already ran under Suse 9.1 and NTP version 4.2.0a

Now I updated the system to Suse 10.2. and NTP version 4.2.2p4 (from scratch

1) Everything works with time servers from the Internet
2) The HopfClock writes a message into the /var/log/warn file and is not
even listed (ntpq -p):

  Feb  8 20:45:07 earth ntpd[15469]: refclock_open /dev/hopfclock0:
Operation not permitted
  Feb  8 20:45:07 earth ntpd[15469]: configuration of failed

I went through the sources, but I couldn't find any clue.

My ntp.conf looks like that:
## Hopf DCF 6020
server  prefer mode 12
fudge  stratum 0
fudge  time1 0.020
fudge  refid DCF77_Hopf
fudge  flag1 1 flag2 0 flag3 0 flag4 0
#fudge  flag1 1 flag2 0 flag3 0 flag4 0 stratum 0 time1 0.02

The soft link to /dev/hopfclock0 is available and I was able to capture the
time signal of the clock with minicom terminal program.
I tried everything with the permissions of the device - without success.

Just for a try I changed to the Parse Clock ( on /dev/refclock-0
with basically the same warning.

I even installed in a quick and dirty act the NTP 4.2.0a version - with the
same results.

What does the message "refclock_open /dev/hopfclock0: Operation not
permitted" exactly mean?

Do I have to compile something into my kernel which is probably not in yet?

I really picked my brain and I suspect it has something to do with my

Any clue is appreciated.


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