System information

Troubleshooting Novell IPX 8-167
Novell IPX: Slow Performance
Novell IPX: Slow Performance
Symptom: Slow network performance is experienced in a Novell IPX network.
Table 8-13 outlines the problems that might cause this symptom and describes solutions to those
problems.
Table 8-13 Novell IPX: Slow Performance
SAP updates dropped from
hub router’s output queue
Slow serial lines can cause the router to drop SAP packets before they are
transmitted.
Step 1 Use the show interfaces serial exec command and examine the output
queue drops field. A large number of dropped packets might indicate that
SAP updates are being dropped before they can be transmitted across the
serial link.
Step 2 Use the show ipx servers exec command on the router. Compare the
output of this command with the output of the display servers system
console command on Novell servers.
Step 3 If the display servers output for a Novell server shows only
a partial listing of the SAP entries shown by the router, the router might be
dropping SAP packets from the output queue.
Step 4 Eliminate the forwarding of any SAP updates that are not absolutely
necessary. Configure filters using the ipx input-sap-filter, ipx
output-sap-filter, and ipx router-sap-filter interface configuration
commands, as appropriate.
Step 5 Increasing the output hold queue on the serial interface might also improve
performance. Use the hold-queue length out interface configuration
command to increase the output hold queue length. The default output
hold-queue limit is 100 packets. The general rule when using the
hold-queue command is for slow links, use a small output hold-queue
limit. This approach prevents storing packets at a rate that exceeds the
transmission capability of the link. For fast links, use a large output
hold-queue limit. A fast link may be busy for a short time (and thus
require the hold queue), but can empty the output hold queue quickly when
capacity returns.
Step 6 If SAP filters and increased queue lengths do not solve the problem,
increase the available bandwidth if possible. Add a second serial line or
obtain a single link with more available bandwidth.
1
Router is stuck in active mode
(EIGRP only)
If you consistently receive “Stuck-in-Active” messages about a particular network,
you probably have a flapping route (typically caused by heavy traffic load). Route
flapping can cause routes to come and go in the routing table, resulting in
intermittent connectivity to some networks.
Take steps to reduce traffic on the link or to increase the bandwidth of the link.
For more information about troubleshooting serial lines, refer to Chapter 15,
“Troubleshooting Serial Line Problems.”
1 If increasing the bandwidth is not possible, buffer management might help alleviate the problem. Contact the Cisco Technical
Assistance Center for assistance in tuning buffers.
Possible Problem Solution