OSF DCE Administration Guide--Core Components

Interoperation with Network Time Protocol
NTP
client
server
stratum 8
server
NTP − s
client
server
stratum 9
NTP
server
stratum 8
server
NTP − s
stratum 10
DTS DTS
DTS
26.3 Preventing Loops
Do not allow loops, such as NTP → DTS → NTP, to form.
Run the null time-provider (dts_null_provider.c) only if you have a local time source.
If you do not have a local time source, you can run the null time-provider, but do not
disseminate NTP time anywhere in the local set.
Figure 26-5 shows a configuration that is not recommended. This configuration works
only as long as the remote NTP Stratum 2 node does not fail.
Figure 26-5. Configuration Before Stratum 2 Node Fails
stratum 8 stratum 3
ntpd −s
stratum 2
remote
NTP server
dts_ntp_provider.c
DTS
server
DTS
server
NTP
server
If the remote NTP Stratum 2 node fails, the Stratum 3 node starts accepting time from the
Stratum 8 node. Once this occurs, the Stratum 3 node drops to Stratum 9 and the Stratum
4 node drops to Stratum 10, as shown in Figure 26-6.
Figure 26-6. Configuration After Stratum 2 Node Fails
124243 Tandem Computers Incorporated 26−5