Operation Manual

Configuring ISDN Call Destinations 135
26. Check the Timesync Filter .
In a NetWare 4 environment, NetWare Directory Services (NDS)
is distributed across the network. When users or objects are
added to the directory, they are added to the local copy of the
database and then propagated throughout the network to other
copies (replicas) of the database. If the same object is modified in
two different replicas, the order of the modification must be
preserved to correctly propagate the changes. One way to ensure
the correct ordering of directory events is to time stamp them.
Without a common time source, each of the NDS servers can
have a different reference time. Time synchronization solves this
problem by synchronizing the time among NDS servers in the
network.
On the network protocol level, you can use the TIMESYNC.NLM
to reduce the frequency in which Time synchronization packets
are sent. For more information, refer to the NetWare MultiProtocol
Router 3.1 Release Notes, pp. 48-50.
The Timesync Filter filters NCP requests type 114 that are used to
synchronize time between NDS servers on the ISDN driver level.
In this case, you have to use a different mechanism to synchro-
nize NDS servers, for example by using external clock devices.
Default: Enabled
Options: Enabled, Disabled
When the Timesync Filter is enabled, NCP requests type 114 are
not sent over ISDN to other NDS servers in the WAN.
When you disable the filter, an ISDN connection is set up each
time if time synchronization packets are issued.
27. Check the NW4/NDS Filter .
In all versions of NetWare 4, the NDS synchronization logic
checks with each server in its replica list regularly to determine
whether any changes have occurred. There are different proc-
esses with different synchronization tasks. Examples are the
Heartbeat, Backlink and Schema process. Each synchronization
is initiated with a so-called Ping-for-NDS packet (NCP request
type 104).