H3C SOHO IE4100, Руководство по устранению неисправностей

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1. Verify that the port is functioning correctly. For more information, see " Layer 2 forwarding
failure " to locate hardware and configuration problems of the port.
{
If the port is faulty, troubleshoot the port problem as described in " Layer 2 forwarding
failure ."
{
If the port is not faulty, go to step 2.
2. Verify that the ARP entries are correct.
Use the
display arp
command to check whether the device has learned the ARP entries of
the gateway and the whether the learned ARP entries are correct.
{
If the device has not learned the ARP entries or learns incorrect ARP entries, use the
debugging arp packet
command to locate the cause. For the ARP entries that are not
learned, you can use the
arp static
command to manually add them.
{
The number of ARP entries has reached the upper limit.
−
If the number of learned ARP entries has reached the upper limit of the system, no more
ARP entries are learned, and the system will return the relevant message.
−
If the number of learned ARP entries has reached the upper limit of the hardware
forwarding resources, exceeding ARP entries are not used for Layer 3 forwarding. Even
though they can be used to forward packets through the CPU, the forwarding efficiency
is very low.
{
If the device has correctly learned the ARP entries, go to step 3.
3. Verify that the route entries are correct.
Use the
display ip routing-table
command to check whether the device has learned
correct route entries.
{
If the device has learned incorrect route entries, use the relevant routing protocol to further
troubleshoot the problem.
{
Overlapping networks exist, for example, 192.168.1.0/24 and 192.168.1.32/27, which are
not supposed to exist in a properly planned network. If the destination address of a packet
matches both networks, typically, the one with longer mask applies to packet forwarding
according to the longest match rule. However, if the packet matches the direct network and
the device has learned the relevant ARP entry, the direct network applies to packet
forwarding.
{
If the number of route entries has reached the upper limit of the hardware resources,
exceeding route entries are not used for Layer 3 forwarding.
4. If the issue persists, contact H3C Support.
Related commands
This section lists the commands that you might use for troubleshooting Layer 3 packet forwarding
failure.
Command Description
debugging arp packet Enables ARP packet debugging.
display arp Displays ARP entries.
display ip routing-table Displays routing table information.