3Com Switch 7750 Configuration Guide Guide

142 CHAPTER 16: IPX CONFIGURATION
Solutions:
■ Check whether there are update packets with the debugging ipx packet and
debugging ipx sap packet verbose commands. Check whether the MTU of the
SAP packets is smaller than the MTU of the VLAN interface to guarantee that
they are not dropped by the underlying layer.
■ Use the display current-configuration command to check whether the
triggered updates feature is configured on the VLAN interface. Periodical
update is disabled when the triggered updates feature applies.
■ Check whether all service information is learnt from the VLAN interface. Then
check whether split horizon is enabled on the VLAN interface.
Symptom 6: SAP does not respond to GNS requests.
Solutions:
■ Use the debugging ipx packet sap command to check whether the switch
receives the GNS packets.
■ Check whether SAP is enabled on the VLAN interface.
■ Use the display ipx interface command to check whether the VLAN interface is
enabled to respond to GNS requests. If GNS reply is disabled, use the undo ipx
sap gns-disable-reply command to enable the interface to respond to the GNS
requests.
■ Use the display ipx service table command to check whether the requested
service information is available in the service information table.
■ If the requested service information is available in the service information table,
but SAP still does not give response, you need to check whether the service
information is learnt from the interface where the request is received.
Symptom 7: SAP does not respond to a GNS request through Round-Robin.
Solutions:
■ Use the display current-configuration command to check whether
Round-Robin is enabled.
■ If Round-Robin is enabled, check whether multiple equivalent service entries
are available for the service request. The service entries are considered
equivalent only when they have the same RIP delay, RIP hop count, SAP hop
count and SAP preference.
Troubleshooting IPX routing management
Symptom 1: The current switch receives the routing information from a neighbor
device, but the route cannot be found on the current switch with the display ipx
routing-table verbose command.
Solutions:
■ Use the display current-configuration command to view the maximum number
of dynamic routes for each destination network number. The corresponding
command is ipx route max-reserve-path. The default value is 4.