OSF DCE Administration Guide--Core Components

Interoperation with Network Time Protocol
Observe the following advisories:
• Advisory—If links to remote sources are distant, consider having one of the
subnetwork nodes run the NTP locally.
• Advisory—Note that the NTP time-provider does not accept time from an NTP node
at Stratum 8 or higher.
• Advisory—The NTP node needs to be as close to Stratum 1 as possible.
Figures 26-2 and 26-3 both show a DTS server getting the time from a remote NTP time
source, which is a Stratum 3 server. However, in Figure 26-2 (Scenario 1), all of the
advisories in this section are followed; in Figure 26-3 (Scenario 2), the first advisory,
running NTP locally on one of the subnetwork nodes if the link to a remote source is
distant, is ignored.
Figure 26-2. Getting the Time from a Remote NTP Time Source (Scenario 1)
local
DECdts DECdts
client
NTP server
server
local
stratum 4
client
NTP server
server
stratum 3
remote
NTP server
serverserver
dts_ntp_provider.c
DTS
DTS DTS
Figure 26-3. Getting the Time from a Remote NTP Time Source (Scenario 2)
server
clientserver
stratum 3
NTP node
remote
dts_ntp_provider.c
DTS
DTS DTS
124243 Tandem Computers Incorporated 26−3