System information

Troubleshooting Novell IPX 8-145
Novell IPX: Clients Cannot Connect to Server over PSN
Novell IPX: Clients Cannot Connect to Server over PSN
Symptom: Clients cannot connect to servers over a packet-switched network (PSN), such as Frame
Relay, X.25, or SMDS. Clients can connect to local servers.
Duplicate network
numbers
Every network number must be unique throughout the entire Novell IPX
internetwork. A duplicate network number will prevent packets from being
forwarded properly.
Step 1 Use the show ipx servers and the show ipx route privileged exec
commands. Check the output of these commands for server addresses that
have been learned from the wrong interface.
For example, if you know that you have a server on the local network with
network number 3c.0000.0c01.2345 and the show command output
shows that this server is located on a remote network, there is probably a
server on the remote network that’s using the same network number.
Step 2 If you suspect a duplicate network number, use a process of elimination to
identify the misconfigured server. This can be difficult, particularly if you
do not have access to every network device in the Novell IPX
internetwork. When you have identified the misconfigured server, modify
the server configuration to eliminate the duplicate network number.
Router hardware
problem
Check all router ports, interface processors, and other router hardware. Make sure
cards are seated properly and that no hardware is damaged. Replace faulty or
malfunctioning hardware.
For detailed information on troubleshooting router hardware problems, refer to
Chapter 3, “Troubleshooting Hardware and Booting Problems.”
Backdoor bridge
between segments
Step 1 Use the show ipx traffic exec command on intermediate routers.
Determine whether the bad hop count field is incrementing.
Step 2 If the bad hop count counter is incrementing, use a network analyzer to
look for packet loops on suspect segments. Look for RIP
3
and SAP
updates as well. If a backdoor bridge exists, you are likely to see hop
counts that increment to 16, at which time the route disappears and
reappears unpredictably.
Step 3 Look for packets from known remote network numbers that appear on the
local network. Look for packets whose source address is the MAC
4
address of the remote node instead of the MAC address of the router.
Step 4 Examine packets on each segment. A back door is present on the segment
if packets appear whose source address is the MAC address of a remote
node instead of that of the router.
Step 5 Remove the backdoor bridge to close the loop.
Routing protocol
problem
Misconfigurations and other routing protocol issues can cause connectivity and
performance problems. For information on troubleshooting specific IPX routing
protocols, see the appropriate section later in this chapter.
1 LIPX = Large Internet Packet Exchange
2 FDDI = Fiber Distributed Data Interface
3 RIP = Routing Information Protocol
4 MAC = Media Access Control
Possible Problem Solution