Novell Documentation: Novell Internet Access Server 4.1

Troubleshooting Tools

The following utilities that can be used to troubleshoot NetWare Link/X.25 links:

X25CON

X25CON is an NLM management console utility that provides access to the interface configuration and statistical information of all X.25 interfaces. It uses SNMP to access this information from a local or remote router on the network.

You can use X25CON to obtain the following information:

Connectivity display

Total number of X.25 interfaces configured

Total number of active X.25 interfaces

Total number of active virtual circuits

SNMP access configuration and control

X.25 interface and activity summary

Packet-layer, Link-layer, and Physical-layer statistics of the X.25 interface

Operating parameters of the Packet layer, Link layer, and Physical layer of the X.25 interface

X.25 call target for the WAN connection

Entries of the cleared circuit table

Local SNMP trap log created by SNMPLOG.NLM

X25CON also provides an X.25 PING diagnostic utility that is used to perform connection checks or troubleshooting of an X.25 data link (available for SVCs only). To perform a PING test on an X.25 destination, select a destination (configured in the WAN call destination database) and press F3 to execute the test.

Upon completion of the test, the X.25 PING displays the following:

Average call setup time

Number of messages transmitted and received

Number of transmit errors and receive errors

Average elapsed time for a message round trip

Cause and diagnostic codes received in the Clear Request/Indication packets if the call setup failed

We highly recommend that you perform a test using X.25 PING to verify X.25 connectivity before you integrate the X.25 interface with the LAN protocol stack.

X25TRACE

X25TRACE is an NLM utility that allows you to view and capture the X.25 traffic in real time. This utility provides the following options:

Network Interface Information---Displays the available X.25 interfaces and the hardware configuration information about each interface, such as port address, interrupt level, and base memory address.

Real-Time Monitor---Enables you to monitor the X.25 traffic on a specific X.25 interface in real time. You can capture the data to RAM or disk. You can display X.25 traffic in raw, frame, or packet mode.

Playback---Replays captured data.

Configuration---Enables you to configure the capturing option, RAM or Disk, and the filename if the data is captured to disk.

X25TRACE also includes a print utility, X25DISP, that reads an X25TRACE capture file and writes the contents to an output file that can be printed or viewed with an ASCII editor or browser. If specified, the contents of the file are converted so that they are displayed in ASCII or hexadecimal format, in complete or short display mode, and in one of three decode modes: raw, frame, or packet mode. Table 4 shows the arguments that can be used with this DOS executable file. These arguments are case-sensitive.

Table 4. X25DISP Arguments

Argument	Meaning
`X25DISP`	Runs the DOS executable file.
`-i<`filename`>`	Specifies the name of the input file.
`-o<`filename`>`	Specifies the name of the output file.
`-a`	Displays the data in ASCII.
`-h`	Displays the data in hexadecimal.
`-c`	Displays the data in complete mode.
`-s`	Displays the data in short mode.
`-m0`	Decodes the data to display in raw mode.
`-m1`	Decodes the data to display in frame mode.
`-m2`	Decodes the data to display in packet mode.

For example, to write the captured data to an output file to display in ASCII, complete mode, and frame mode, enter the following command:

X25DISP -i filename -o filename -a -c -m1

MONITOR

The LAN/WAN Information option of MONITOR allows you to monitor the various statistics of LAN or WAN drivers. For the X.25 interface, there are several X.25 interface statistics displayed only by MONITOR. These include the following:

No ECB Available Count---Number of times the message transmission or reception failed because an ECB is not available.

Send Packet Too Big Count---Number of times the message transmission failed because the packet size was greater than the specified maximum packet size.

Receive Packet Too Big Count---Number of times the message reception aborted because the received packet size was greater than the specified maximum packet size.

Checksum Error---Number of times a checksum error occurred.

Over Queue Limit---Number of times a transmit message was discarded because of the queue overflow condition. You can configure the Transmit Queue Limit parameter by loading NIASCFG and selecting Protocols and Routing > Network Interface.

Loopback Tests

When you experience an X.25 link failure, we recommend performing one or more of the three loopback tests described in this section, depending on the nature of the problem. This testing can help you identify the cause of the failure.

Dual-Port Loopback Test

To perform this test, connect two ports of a server through a modem eliminator, a modem, a DSU/CSU, or crossover cables. The loopback test is performed with X.25 PING in X25CON.

Loopback Test to the Local DTE Through a PDN

You can perform this loopback test when the server is connected to the X.25 public data network (PDN). You can perform an X.25 PING test to any remote server running the routing software that is connected to the X.25 PDN. Connect a port to the PDN, then establish a virtual circuit back to the originating port by calling the local DTE with X.25 PING in X25CON.

Loopback Test to the Remote DTE Through a PDN

Execute this loopback test when the source and destination DTEs are connected to the X.25 PDN. You can perform an X.25 PING test to any remote server running the routing software that is connected to the X.25 PDN.