H3C Technologies H3C MSR 50 - Manual (Page 20)

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• Check whether the number of SAP service information items reaches the upper limit. The IPX
implementation supports up to 10240 service information items and 2048 service types.
• The MTU of SAP should be less that of the physical layer.
No updates are received on an interface
• Use the debugging ipx packet and debugging ipx sap packet verbose commands to check packet
contents. All incoming and outgoing packets are displayed in debugging information. If no related
packets are displayed, problems in lower layer network connection might exist.
• Use the display ipx interface command to make sure SAP is enabled on the interface.
• Make sure the active route to the server has a hop number less than 16.
• Use the display current-configuration command to check whether the updating interval is too long.
No updates sent out an interface
• Use the debugging ipx packet and debugging ipx sap packet verbose commands to check packet
contents. If such update packets are displayed in debugging information, possibly the SAP MTU is
larger than the interface MTU. Hence, the packets are discarded by the lower layer.
• Use the display ipx interface command to check whether the interface is enabled with triggered
update. If so, the interface will not periodically broadcast update packets.
• If no SAP packets are sent out the interface, check whether all service information is learned from
the interface. If so, split horizon might be the reason that no service information is sent out the
interface.
SAP does not respond to GNS requests
• Use the debugging ipx sap packet command to check whether GNS request packets are received.
• Make sure SAP is enabled on the receiving interface.
• Use the display ipx interface command to check whether the interface is disabled from responding
to GNS requests. If so, use the undo ipx sap gns-disable-reply command to enable the interface.
• Use the display ipx service-table command to check whether the requested service information is
available in the SIT table. If not, SAP will not respond.
• If the requested service information is available, check whether the service information is learned
from the interface that received the GNS requests. In that case SAP will also not respond to the GNS
requests.
SAP does not respond to GNS requests in the Round-robin mode
• Use the display current-configuration command to make sure Round-robin is configured.
• If Round-robin is configured, verify whether multiple equivalent service information items exist for
the service type of the requests. The equivalent service information items must have the same RIP
ticks, RIP hops, SAP hops and SAP preference.
Troubleshooting IPX routing management
No dynamic routing protocols are configured on the device
The physical status and link layer protocol are both UP on an interface, but IPX packets cannot be
forwarded correctly:
• Use the display ipx routing-table protocol static command to check whether a correct static route is
configured.