Netgear XCM8810 - 8800 SERIES 10-SLOT CHASSIS SWITCH ユーザーズマニュアル

Troubleshooting Checklists

This section provides simple troubleshooting checklists for Layer 1, Layer 2, and Layer 3. 
The commands and recommendations described are applicable to both IPv4 and IPv6 
environments unless otherwise specified. If more detailed information about a topic is 
available, you are referred to the applicable section in this appendix.

Layer 1

When troubleshooting Layer 1 issues, verify:

The installation of cables and connectors.

The behavior of LED status lights. For additional information about LEDs, see 

That the port is enabled, the link status is active, and speed and duplex parameters match 

the port settings at the other end of the cable. 

To display the configuration of one or more ports, use the 

show ports configuration

 

command.

That the packets are being received and transmitted.

To display the number of packets being received and transmitted, use the 

show ports 

{<port_list> | stack-ports <stacking-port-list>} statistics {no-refresh}

 

command.

That there are no packet errors.

To display packet error statistics, use the following commands:

show ports {<port_list> | stack-ports <stacking-port-list>} rxerrors 

{no-refresh}

—Displays receive error statistics

show ports {<port_list> | stack-ports <stacking-port-list>} txerrors 

{no-refresh}

—Displays transmit error statistics

show ports {mgmt | <port_list>} collisions {no-refresh}

—Displays collision 

statistics

Layer 2

When troubleshooting Layer 2 issues, verify:

That the MAC addresses are learned, in the correct Virtual LAN (VLAN), and are not 

blackhole entries.

To display FDB entries, use the 

show fdb

 command. 

Your VLAN configuration, including the VLAN tag, ports in the VLAN, and whether or not 

the ports are tagged.