HP-UX Internet Services Administrator's Guide (February 2007)

Setting up a Spectracom Netclock/2.........................................................................50
Location of Time Source....................................................................................................51
Example 1: Locating the Best Primary Server ................................................................52
Determining Synchronization Sources..........................................................................53
Example 2: Evaluating Time Servers in Eastern United States.........................................53
Example 3: Evaluating Time Servers in Australia...........................................................54
Backup Time Servers........................................................................................................56
The NTP Daemon.............................................................................................................56
The NTP Configuration File..............................................................................................57
Configuring Your Primary NTP Server...............................................................................58
Advanced NTP Topics............................................................................................................59
Stratum Levels and Time Server Hierarchy.........................................................................59
Stratum-1 Time Servers................................................................................................59
Stratum-2 and -3 Time Servers.....................................................................................60
Time Server Roles........................................................................................................60
Planning a Multiple-Server NTP Configuration..................................................................61
Configuring NTP using the Configuration File...................................................................62
Configuring Relationships with Other Time Servers......................................................62
Configuring an External Clock.....................................................................................64
Configuring a Driftfile.................................................................................................65
Configuring Authentication.........................................................................................66
Restricting Incoming NTP Packets.....................................................................................68
Starting and Stopping xntpd.............................................................................................69
Using ntpq to Query Systems Running xntpd.....................................................................70
Verifying ntpq.............................................................................................................70
The ntpq Program Output...........................................................................................70
Troubleshooting NTP.............................................................................................................72
Verifying That xntpd is Running........................................................................................72
NTP Associations.............................................................................................................73
Query with Debug Option.................................................................................................73
Error Messages.................................................................................................................74
No server suitable for synchronization found................................................................74
Last adjustment did not complete.................................................................................74
Synchronization lost....................................................................................................74
Common Problems...........................................................................................................74
Problem 1: No suitable server for synchronization found...............................................74
Time Difference Greater than 1000 seconds..............................................................75
Startup Delay........................................................................................................76
Problem 2: Version 1 and 2 NTP Servers Do Not Respond..............................................76
Reporting Problems..........................................................................................................76
5 Troubleshooting Internet Services................................................................................................77
Troubleshooting Overview.....................................................................................................77
Table of Contents 5