LAN Manager Trouble-Shooting Guide

ID Number: Q69880

2.00

OS/2

Summary:

LAN Manager Trouble-Shooting Guide

==================================

This guide is a general starting place for resolution of common

problems encountered when setting up LAN Manager for the first time or

changing to a new configuration. Most problems or errors found with

LAN Manager can be placed in one of the first three categories listed

below. Common solutions for each category are listed at the end of

this article.

CATEGORIES

----------

A. Incorrect Hardware Configuration

B. Incorrect Software Setup

C. Lack of Server Resources (Software or Hardware)

D. Other

SIMPLE TESTS

------------

Four easy tests to narrow down the problem into one of these

categories are:

1. Check Server Error Log

Check the server error log for information on what might be causing

a problem. Most resource problems (e.g. lack of memory or disk

space) will produce errors in the log (category C).

2. Net Send Test

This test checks the connection between the server and workstation.

After starting the server and a workstation, verify that you can

send a message from a workstation to the server (net send

<computername> message). If this test fails you may have an

incorrect hardware configuration (category A). This test is not

applicable for DOS Basic workstations.

3. Loopback Driver Test

This test will allow you to distinguish between hardware and

software problems on the server. It can only be used for errors in

starting up the server or services. This test does not work for

connection problems between machines.

If appropriate, replace the specific card driver and protocol stack

with the "loopback driver" using the setup program. Reboot the

server and attempt to reproduce the problem. If you are still

having the same error, the problem is most likely related to the

software (category B). If the problem goes away, most likely it was

a hardware configuration problem (category A).

4. Diagnostic Programs

Use network card manufacturer's diagnostic programs to check for

hardware problems (category A).

COMMON SOLUTIONS

----------------

A. Incorrect Hardware Configuration

1. Interrupt, I/O address, base address, or DMA channel conflicts

may exist between the network card and another device. Use a

manual or a diagnostic program to determine the current setting.

Change the setting so that it is different from other devices.

2. The physical network connection could be incomplete, or there is

a problem with the local network cable plant. Use diagnostic

programs or equipment to troubleshoot the local cable plant.

3. A memory conflict may exist. Since DOS LAN Manager is a

memory-resident program, it may be in conflict with other

programs which stay resident in memory. Check for TSRs or

unneeded device drivers. Remove all unnecessary lines in

AUTOEXEC.BAT and CONFIG.SYS.

B. Incorrect Software Setup

1. The MAC driver may not be configured correctly (etherlink II is

an example of a MAC driver). Check the section in the Network

Device Driver Guide for your driver. Verify that all of the

parameters in protocol.ini match your card configuration. Make

sure the driver is listed as being compatible with the card you

are using.

2. Machines on the network may not be using the same protocol

stack. Check to make sure that the protocol stacks match on the

two machines that are trying to communicate (netbeui is an

example of a protocol stack).

3. Inter-Process Communication (IPC$) may not be shared on the

server. This is a common problem for share-level security

servers. IPC$ is automatically shared for user-level security

servers. Share IPC$ on the server.

C. Lack of Server Resources (Software or Hardware)

1. The server may run out of resources if too much cache is

allocated. Adjust the amount of cache allocated for the server

in config.sys.

2. The server may run out of NetBIOS sessions, NCBs, or names. See

p.19 of the LAN Manager Network Device Driver Guide to adjust

these parameters.

3. The server may not have enough physical memory. See p.7 of the

installation guide for memory requirements. Add memory to the

server if necessary.

D. Other

1. Try going back to a configuration that is as generic as

possible. Use the setup program to save the configuration and

only make necessary changes. Otherwise, use the defaults.

2. Check the LAN Manager Manuals. The LAN Manager Administration

Guide has very good descriptions of how to set up your LAN.

Chapter 4 on security is particularly useful if you are having

trouble setting up your server and domain.