Alcatel Carrier Internetworking Solutions Omni Switch/Router - Manual (Page 821)

Configuring NetWare to Minimize WAN Connections
Page 27-33
Configuring NetWare to Minimize WAN Connections
If you have access to NetWare’s control parameters, you can “fine-tune” your network to
minimize traffic on WAN links such as ISDN connections or Frame Relay lines. Doing so will
reduce the costs associated with each connection that is made. Some suggested approaches
are described below.
1. NetWare Directory Services (NDS), included in NetWare 4.x, includes a time synchroniza-
tion protocol. By default, NetWare servers send time synchronization packets every 10
minutes. To help cut down on unnecessary connections that result from the time synchro-
nization protocol, you could load the NLM (NetWare Loadable Module) named
TIME-
SYNC.NLM onto your NetWare time servers. This NLM will allow you to modify the update
interval of the time synchronization packets.
2. NDS also introduces more traffic in order to maintain replicas of NDS partitions. The NLMs
named DSFILTER.NLM and PINGFILT.NLM can be used to modify NDS synchronization
updates.
3. NetWare’s IPX Watchdog protocol monitors the connection status of NetWare clients and
transmits reports when a connection fails to respond. You could modify the following
three Watchdog parameters on your NetWare file servers to help cut down the costs asso-
ciated with the IPX protocol:
• SET NUMBER OF WATCHDOG PACKETS (the default is 10, range is 5 to 100 packets).
• SET DELAY BETWEEN WATCHDOG PACKETS (the default is 59.3 seconds, range is 9.9
seconds to 10 minutes and 26.2 seconds).
• SET DELAY BEFORE FIRST WATCHDOG PACKET (the default is 4 minutes 56.6 seconds,
range is 15.7 seconds to 20 minutes and 52.3 seconds).
4. There are two basic categories of timeouts which can cause extra network traffic and/or
loss of SPX connections:
• If a data packet goes unacknowledged, it is re-transmitted a certain number of times
before the connection is aborted.
• When a connection is idle and the SPX Watchdog is enabled, system packets are sent
periodically, and if not eventually acknowledged, the connection is aborted.
5. The following parameters can be modified in the NET.CFG file to determine when pack-
ets should be resent or when connections should be aborted:
• MINIMUM SPX RETRIES determines how many unacknowledged transmit requests are
allowed before assuming the connection has failed.
• SPX VERIFY TIMEOUT determines how often (in ticks) the SPX protocol sends a packet
to the other side of a connection to indicate that it is still alive.
• SPX LISTEN TIMEOUT specifies how long (in ticks) the SPX protocol waits without
receiving a packet from the other side of the connection before it requests the other
side to send a packet to ascertain whether the connection is still valid.
• SPX ABORT TIMEOUT specifies how long (in ticks) the SPX protocol waits without
receiving any response from the other side of the connection before it terminates the
session.