Specifications

APPENDIX A. INSTALLATION 31
clock test/clock test 1 3 which sends the command ”3” (READ TIME) to board
number 1 (the first board /dev/hslclock0 ). Then you can run dump hslclock.sh 1 to
see if the clock is counting.
NOTE: In order for the clock card to work, it has to be connected to the 10MHz signal
from the GPS card – otherwise the counter does not change.
A.4.3 The manager program – HS MASTER
If the GPS and the clock are working fine then you can configure the hs master program
from the directory hsmaster . First you have to install hs daemon on each computer
involved in the synchronization process. For this you have to configure the (x)inetd
server to load hs daemon when a request at some port is made.
A simple way to configure xinetd is to copy the files from directory hsmaster/xinetd -
config to the directory /etc/xinetd.d . You may need to modify those files ( hs daemon
and hs daemon1 ) to specify the correct path to the hs daemon executable (on the line
”server = ....”). This path should be readable by all users. If you have problems please
refer to [4] for more details about this configuration.
NOTE: A hs daemon program should be installed on all the nodes that require syn-
chronization and have a clock card inside, INCLUDING the ”master” node. T he program
creates also some log files in the /tmp directory on the local machines ( hsdaemon -
log*.txt and hsdaemon results*.txt )
The master node is the node that hosts the GPS card. On this computer you will run the
hs master program. While hs daemon is an executable that can b e placed in /usr/bin
on all the computers, hs master requires the presence of the program hs client in the
same directory as itself. It also requires the presence in the same directory of a configuration
file called hs nodes.conf . This file has lines of the form hostname:port listing all the
hostname : port combinations that correspond to local clock cards. DON’T FORGET to
list here the clock card in the master itself or it will be left out in all the operations!
An example of the contents of the hs nodes.conf could be:
pcstuff01.cern.ch:40000
pcstuff01.cern.ch:40001
pcstuff02.cern.ch:40000
Note that pcstuff01.cern.ch has two clock boards inside and it uses different ports for each
card. pcstuff02.cern.ch has a single card and uses port 40000.
NOTE: Important: You have to create a different hs nodes.conf file for each local
group of computers (site) that depends on a GPS card. Don’t list in this file machines from
other groups. On each master of each group you should run an instance of the hs master
program with a different configuration file.
To check that the system is working you can open a terminal window with dump -
hslclock.sh and use the Simple Synchronize option in hs master to see if the clock is
reset at some point (do not use the PPS Sync Thread option for this). Then you can use
the global synchronization tests to verify the whole system.