NetWare Directory Services

5-10
Understanding Time Synchronization in NDS
Time Source Server Functions
Time Source Server Functions
The Single Reference, Primary, and Reference time servers are all time
source servers. That is, they provide time to the network. Secondary servers
do not provide a time to other servers; they only receive a time from a time
source server. (They do, however, provide time to client workstations.)
Time source servers use one of two methods to find each other: SAP or
custom configuration.
SAP (Service Advertising Protocol)
By default, Primary, Reference, and Single Reference time servers use SAP
to announce their presence on the network.
Primary and Reference time servers use the SAP information to determine
which other servers to poll in order to determine the network time.
Secondary time servers use the SAP information to choose a time server to
follow.
An advantage of the SAP method is that it allows for quick installation
without regard to the network layout. It also allows automatic
reconfiguration if operating modes are changed or if new servers are added
to the network.
CAUTION: The SAP method might generate additional network traffic.
The SAP method might also be disruptive in large network environments where
“test” servers come and go, especially if the test server is configured as a time source
(Single Reference, Reference, or Primary time server).
Custom Configuration
Custom configuration of your time servers might give you more control over
time synchronization, but it requires more planning to synchronize servers
efficiently.