Alcatel Carrier Internetworking Solutions 6648 - Manual (Page 123)

Troubleshooting Link Aggregation Troubleshooting a Link Aggregation Failure
OmniSwitch Troubleshooting Guide September 2005 page 7-3
Troubleshooting a Link Aggregation Failure
Link Aggregation Setup
The figure above has the following setup:
• Switch A and Switch B connected back to back and Link Aggregation configured.
• Port 7/1 of Switch A is connected to port 7/1 of Switch B.
• Port 7/2 of Switch A is connected to port 7/2 of Switch B.
• VLAN 10 is assigned to this aggregate.
• PC1 connected to Switch A slot/port 1/5.
• PC2 connected to Switch B slot/port 1/5.
Verify the Configuration
First, verify that the ports and aggregates involved are assigned correctly. The CLI command show
linkagg will confirm that the aggregates are configured and are enabled and up as shown below:
-> show linkagg
Number Aggregate SNMP Id Size Admin State Oper State Att/Sel Ports
-------+----------+---------+----+------------+--------------+-------------
2 Dynamic 40000002 8 ENABLED UP 2 2
3 Static 40000003 2 ENABLED UP 2 2
The show linkagg command followed by the aggregation number will show the aggregate state, size,
number of active ports, number of inactive ports, as well as the primary port. (See the sample below.) Note
also the primary port is the port that spanning tree runs on. It is important to verify that this port is not
changing regularly as that could cause spanning tree problems.
-> show linkagg 3
SNMP Id : 40000003,
Aggregate Number : 3,
SNMP Descriptor : Omnichannel Aggregate Number 3 ref 40000003 size 2,
Name : ,
Admin State : ENABLED,
Operational State : UP,
Aggregate Size : 2,
Number of Selected Ports : 2,
Number of Reserved Ports : 2,
Number of Attached Ports : 2,
Primary Port : 7/1
OmniSwitch 7800 OmniSwitch 7800
Switch A Switch B