Technotools/Technotools (Chestnut CD-ROM)(1993).ISO/lantools/an009a/an009a.txt

Text File | 1991-01-10 | 16KB | 349 lines

TRACK [ON/OFF] Console Command, Syntax and Applications

 J. Warren Harding
 Research Manager
 Systems Engineering Division

Abstract:

The TRACK console command is an undocumented diagnostic tool that can be
invoked on any file server running 286-based NetWare or NetWare 386 or
router (formerly NetWare Bridge) console. Not only is it a very useful
tool to investigate problems associated with workstations attempting to
connect to a server, but TRACK gives you the ability to diagnose problems
with routers and servers on the internetwork. It displays routing and
server information that can be helpful in diagnosing and preventing
network problems. This Appnote discusses the use, syntax and diagnostic
applications of TRACK information.

Disclaimer

Novell, Inc. makes no representations or warranties with respect to the
contents or use of these Application Notes, or any of the third-party
products discussed in the AppNotes. Novell reserves the right to revise
these Application Notes and to make changes in their contents at any
time, without obligation to notify any person or entity of such revisions
or changes. These AppNotes do not constitute an endorsement of the third-
party product or products that were tested. The configuration or
configurations tested or described may or may not be the only available
solution. Any test is not a determination of product quality or
correctness, nor does it ensure compliance with any federal, state or
local requirements. Novell does not warranty products except as stated in
applicable Novell product warranties or license agreements.

Copyright { 1990 by Novell, Inc., Provo, Utah. All rights reserved.

As a means of promoting NetWare Application Notes, Novell grants you
without charge the right to reproduce, distribute and use copies of the
AppNotes provided you do not receive any payment, commercial benefit or
other consideration for the reproduction or distribution, or change any
copyright notices appearing on or in the document.

Introduction

The use of the TRACK command provides three types of information: route
information, server information and workstation connection requests.
Although the TRACK command is available in both 286-based NetWare and
NetWare 386 they differ only in how the information is displayed.

TRACK is invoked by typing TRACK ON at the file server or router
console.The screen clears and the routing and server information is
displayed as it is received. The function can be turned off by typing
TRACK OFF at the console.

With NetWare 386, use of the ATL-ESC and CONTROL-ESC keys allow toggling
between the TRACK screen and the current screen displayed. Also, you can
stop scrolling of the TRACK screen by pressing any key. Pressing any key
again will cause the TRACK screen to continue. 286-based NetWare does not
support this toggle-pause function.

Fig. 1 illustrates a TRACK display for 286-based NetWare. The NetWare 386
TRACK is displayed in Fig 2.

: 286-based NetWare TRACK screen

: 386-based TRACK screen

Route Information

In order for NetWare to send packets of information through an
internetwork of workstations, file servers and routers, all of these
devices must be informed of existing networks and how information can be
routed to them. Knowledge about the layout of the network is communicated
through the network using the Routing Information Protocol (RIP).
Periodically, information is transmitted between the routers and servers
to inform them of other networks that exist in the internetwork. These
information broadcasts can be displayed using the TRACK function. For
more information on RIP, see the AppNote entitled NetWare Communication
Processes.

Route Information Syntax

Route information is displayed in the following format on 286-based
Netware file servers and routers:

Direction [LAN:Node_Addr]  Net_Num Hops/Ticks  Net_Num Hops/Ticks ...

NetWare 386 displays route information in a slightly different format as
shown below:

Direction [Net_Addr:Node_Addr]  Time  Net_Num Hops/Ticks  Net_Num
Hops/Ticks ...

Direction specifies whether the information is being received from the
network (IN) or whether the server or router transmitted information
(OUT.)

LAN displays the server or router LAN card that received or transmitted
information. LAN is displayed as the letter corresponding to the
respective LAN board (A, B, C or D).

Net_Addr is the eight digit hexidecimal network number assigned to the
LAN board that received or transmitted information. NetWare 386 displays
the network number assigned to the LAN board rather than a LAN letter.

Node_Addr is the node address of the card (12 hex digits) in the server
or router that received or transmitted information. In most OUT
transmissions, the Node_Addr is FFFFFFFFFFFF. This indicates that the
transmission has been broadcast to all nodes on the local network.

Time is displayed in hours, minutes and seconds that the whether
information was received or transmitted. This information is only
displayed on NetWare 386 file servers.

Net_Num is the unique eight digit hexadecimal number assigned to a
specific network. With NetWare, each cabling system on the internet must
be assigned a unique network number. These network numbers are broadcast
by all routers (and file servers) to all other routers and file servers
on the internetwork. In NetWare 386 servers, the information about the
server's internal network number is included in route information
broadcasts.

Hops is the number of routers (internal and external) that a packet would
traverse to reach the network number named. In a NetWare internetwork, a
maximum of 15 hops (or routers) may be traversed before the packet is
discarded.

Ticks denotes the time (in 1/18th of a second increments) that a packet
takes to reach the specified network if a packet were transmitted from
the machine displaying the track-on. Typically this number is very low,
but it can be as high as 999 for a very slow link. This number is used to
differentiate between routes with extremely different transmission
speeds. For all local area network protocols (such as Arcnet, Ethernet
and Token-Ring) the number of ticks required is computed as one tick per
hop. For asynchronous or X.25 routes, the number of ticks is computed
based on the BAUD rate used. The formula is typically:

The number of ticks = 4 * Typical one-way transport time (in 1/18th
second increments) + 10.

As a workstation logs into a specific resource, the estimated number of
ticks to reach that resource is used by the shell to set the initial
time-out for detecting error conditions when communicating with that
resource. Route information held in each of the file servers and routers
is aged by the systems. This information is purged after three minues if
it has not been updated by route information from other routers and
servers.

Multiple Routes

When two routes to a destination are known by a router, the router will
send packets by the fastest route. The route is determined by the ticks
value. If two routes exist with the same transport times, the packets
will be sent out on the first network number in the file server or router
table.

A workstation, however, does not switch to a faster route should one
become available. Instead it relies on the route given by the first
router that responds to a Get Target (get route to a destination)
request. It continues to use that route as long as it is available.

In addition, workstations on the network can query a file server or a
router with a Route Request. These also show up on the TRACK screen.
Examples on 286-based NetWare are shown Fig. 3.

: 286 Workstation TRACK

On large internetworks, the messages can wrap around to several lines. In
the first message in Fig. 3, information is received on LAN A (card node
address 02608C247894) about two networks, numbers 00001EF0 and 00000001.
They are respectively 1 and 3 hops, and 2 and 4 ticks away from the
server or router where the message is displayed.

In the second message in Fig. 3, a broadcast is being sent out on LAN B
with information about network numbers 00003333, 44444444, BABEBAAA, and
12E00000. NetWare 386 displays these with slight differences as shown in
Fig. 4.

: 386 Workstation TRACK

Server Information

Servers in a NetWare internetwork are tracked in a manner similar to
routers and workstations. Information about each server in the
internetwork is transmitted through the network using the Server
Advertising Protocol (SAP). Each file server and bridge maintains tables
of the available servers. The tables are used to route packets to them
and to respond to workstation inquiries regarding the services that are
available in the internetwork.

Server Routing Syntax

As with the RIP, information is periodically (once per minutes)
transmitted between the routers and servers to inform them of other
servers that exist in the internetwork. These information broadcasts can
be displayed using the TRACK function. For more information on SAP, see
the NetWare Application Note entitled NetWare Communication Processes.

Server information is displayed in the following format on 286-based
NetWare file servers and routers:

Direction [LAN:Node_Addr]   Server_Name   Hops   Server_Name   Hops ...

NetWare 386 displays server information as follows:

Direction [Net_Addr:Node_Addr] Time Server_Name Hops Server_Name Hops ...

For complete definitions refer to Routing Information Syntax.

Server_Name is the name of a server on the internetwork for which
information is being propagated. This may include the name of the server
or router (if a LAN to LAN router) that is currently displaying the
TRACK. The server names displayed include the names of all devices or
processes on the internetwork that advertise their services using the
Service Advertising Protocol (SAP). All File Servers and LAN to LAN
routers will be shown. In addition, any VAPs or value-added servers (such
as database servers, job servers or print servers) that advertise their
services using the SAP protocol will also be displayed by TRACK. Examples
are shown in Fig. 5.

: Server TRACK

On large internetworks these messages can wrap around to several lines.
In the first example, information is being received on LAN A (card node
address 02608C247894) regarding three fileservers named FILESERVER1,
FILESERVER2 and FILESERVER3. They are respectively 3, 4 and 1 hop away
from the server or router where this message is  displayed.

In the second example, a broadcast is being sent out on LAN B with
information about server SERVERA (which is itself) and server SERVERB.
NetWare 386 displays this information with slight differences as shown in
Fig. 6.

: A 386 Server TRACK

Get/Give Connection Request

The third type of information that TRACK displays is the get/give
connection requests. These will only be displayed on a file server
console and not on router consoles.

As a workstation boots and loads the NetWare shell, a Get Nearest Server
request is broadcast on the network. All connected file servers will
receive the message and respond back to the workstation with a Give
Nearest Server response. This provides the workstation with a file server
connection. The workstation will initially attach to the first file
server that responds.

The file server TRACK function will display the Get Nearest Server and
Give Nearest Server requests and responses as the file server receives
and responds to them. 286-based NetWare displays these functions in the
following format.

 Direction [LAN:Node_Addr]   Get Nearest Server
 Direction [LAN:Node_Addr]   Give Nearest Server Server_Name

Server_Name is the name of the server that has offered a connection to
the workstation. Fig. 7 shows an example of a 286-based TRACK display.

: 286-based Server Information

The first line is the request for a server connection from the
workstation. The second line is the server named SERVER3 offering the
workstation a connection. NetWare 386 displays these lines with slight
differences as shown in Fig. 8.

 Direction [LAN:Node_Addr] Time         Get Nearest Server
 Direction [Net_Addr::Node_Addr]  Time  Give Nearest Server Server_Name

: 386-based Server

Using TRACK for Diagnostic Purposes

TRACK is useful for diagnosing problems with the network. It can help to
narrow the field when a problem occurs. The applications that follow
identify two problems that might occur on a NetWare network, and ways to
use TRACK to diagnose the cause.

Application 1: File Server Could Not Be Found

Symptoms. The workstation loads the shell and hangs or gets the error A
file server could not be found.

Indication. This indicates that there's a problem with the workstation's
ability to communicate with the file server.

Solution. Before loading the shell on the workstation, activate TRACK on
the file servers and routers involved. As the shell loads on the
workstation, information similar to that shown in Fig. 9 should be
displayed on one of the servers or routers (for 286-based NetWare).

: Loading Shell (286-based NetWare)

For 386 versions of NetWare it will appear as shown in Fig. 10.

: Loading Shell (NetWare 386)

If the file server or router displays all of this information it
indicates that the workstation was able to send requests to the file
server (Get Nearest Server), and the file server was able to answer (Give
Nearest Server). Because the Route Request was transmitted by the
workstation the first response by the server (Give Nearest Server) was
received and understood by the workstation. This sequence of TRACK
messages will be displayed if a workstation successfully loads the shell
and begins to work with a file server.

If none of the above lines of information are displayed on any file
servers or routers on the network as a workstation loads the shell, the
workstation could not successfully send a Get Nearest Server request to
the file server. This could indicate a bad cable system, a bad hub or
concentrator, or an improper connection or termination. It could also be
caused by an improperly configured network adapter or adapter driver.

If only the first line (Get Nearest Server) is displayed as a workstation
attempts to load the shell, the workstation is able to send the request
properly and the file server is able to receive it. However, the file
server is not able to send the response back. This might indicate a
transmission problem in the file server. For example, it might have a
faulty or improperly configured network adapter or adapter driver. The
file server might not have too few file service processes. The cable
system is probably not at fault since the original request was
transmitted without problems.

If the first two lines are displayed (Get and Give Nearest Server) but
the workstation fails to complete the shell load, the workstation sends
OK and the file server receives OK. But if the file server is not sending
properly (and it doesn't know it) or the workstation is not receiving
properly, a bad or improperly configured workstation, or file server
network adapter or adapter driver may be causing the problem.

Application 2: Unknown File Server

Symptoms. A file server is running but cannot be seen when a workstation
initiates the  SLIST command from another server. The error message
"Unknown file server" is displayed when a user attempts to log in to the
server.

Indication. A similar situation occurs when a file server is not
receiving information on other servers or networks in the internet.

Solution. Activate TRACK on all the file servers and printers involved.
Check for information being sent and received by respective servers.
Having improper network numbers configured on a server or router can also
cause this failure. This special case can be identified because errors
such as "WARNING!!! MULTIPLE ROUTER WITH SAME INTERNET ADDRESS!" or
"ROUTER CONFIGURATION ERROR!!! Router xxxxxxxxxxxx claims LAN A is
yyyyyy!" will appear on all of the file servers and routers on the
network.