Troubleshooting guide

12-17
ATM and Layer 3 Switch Router Troubleshooting Guide
OL-1969-01
Chapter 12 Troubleshooting Layer 2 Interfaces
Troubleshooting Fast EtherChannel Problems
Your switch router supports Fast EtherChannel (FEC) and Gigabit EtherChannel (GEC).
Cisco Fast EtherChannel technology builds upon standards-based 802.3 full-duplex Fast Ethernet to
provide a reliable high-speed solution for the campus network backbone. Fast EtherChannel provides
bandwidth scalability within the campus by providing increments of 200 Mbps to 800 Mbps.
Cisco Gigabit EtherChannel technology provides bandwidth scalability within the campus by providing
increments of 2 Gbps to 8 Gbps.
Note EtherChannel does not support IP/IPX filtering at Layer 3 with the ACL daughter card.
Note For more detailed information about EtherChannel, refer to the “Configuring LAN Interfaces”
chapter in the Cisco IOS Interface Configuration Guide.
Troubleshooting Bridging Over Fast EtherChannel
To troubleshoot the EtherChannel status and configuration, use the following commands:
Follow these steps to troubleshoot the EtherChannel status and configuration:
Step 1 Use the show interfaces port-channel number command to confirm the EtherChannel status and
configuration.
Switch# show interfaces port-channel 1
Port-channel1 is up, line protocol is up
Hardware is FEChannel, address is 0010.073c.0513 (bia 0000.0000.0000)
MTU 1500 bytes, BW 300000 Kbit, DLY 100 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive set (10 sec)
Unknown duplex, Unknown Speed
ARP type: ARPA, ARP Timeout 04:00:00
No. of active members in this channel: 3
Member 0 : FastEthernet1/0/4 , Full-duplex, 100Mb/s
Member 1 : FastEthernet1/0/6 , Full-duplex, 100Mb/s
Member 2 : FastEthernet1/0/7 , Full-duplex, 100Mb/s
Last input 00:00:00, output never, output hang never
Last clearing of "show interface" counters never
Queueing strategy: fifo
Output queue 0/120, 0 drops; input queue 0/225, 0 drops
5 minute input rate 13000 bits/sec, 17 packets/sec
Command Purpose
show interfaces port-channel number Displays the status of the physical
interface.
show epc fe-channel interface {fastethernet |
gigabitethernet} slot/subslot/port channel
port-channel number
Displays all EPC interface information
for the specific interface and port
channel.
show epc if-entry interface {fastethernet |
gigabitethernet} slot/subslot/port entry
port-channel number
Displays interface entry information for
the specific interface.