Port Channel Troubleshooting - Edge-Core ES4624-SFP Basic Management Manual

SwitchA (Config-If-Ethernet1/2)#exit
SwitchA (config)#interface eth 1/3
SwitchA (Config-If-Ethernet1/3)# port-group 1 mode on
SwitchA (Config-If-Ethernet1/3)#exit
SwitchA (Config-If-Ethernet1/4)# port-group 1 mode on
SwitchA (Config-If-Ethernet1/4)#exit
SwitchB#config
SwitchB (config)#port-group 2
SwitchB (config)#interface eth 1/1-4
SwitchB (Config-Port-Range)#port-group 2 mode on
SwitchB (Config-Port-Range)#exit
Configuration result:
Add ports 1, 2, 3, 4 of Switch 1 to port-group 1 in order, and we can see a group in
"on" mode is completely joined forcedly, switch in other ends won't exchange LACP
BPDU to complete aggregation. Aggregation finishes immediately when the command to
add port 2 to port-group 1 is entered, port 1 and port 2 aggregate to be port-channel 1,
when port 3 joins port-group 1, port-channel 1 of port 1 and 2 are ungrouped and
re-aggregate with port 3 to form port-channel 1. (It should be noted that whenever a new
port joins in an aggregated port group, the group will be ungrouped first and
re-aggregated to form a new group.) Now all four ports in both SwitchA and SwitchB are
aggregated in "on" mode and become an aggregated port respectively.

8.6 Port Channel Troubleshooting

If problems occur when configuring port aggregation, please first check the following
for causes.
Ensure all ports in a port group have the same properties, i.e., whether they are in
full-duplex mode, forced to the same speed, and have the same VLAN properties,
etc. If inconsistency occurs, make corrections.
Some commands cannot be used on a port in port-channel, such as arp, bandwidth,
ip, ip-forward, etc.
When port-channel is forced, as the aggregation is triggered manually, the port
group will stay unaggregated if aggregation fails due to inconsistent VLAN
information. Ports must be added to or removed from the group to trigger another
aggregation, if VLAN information inconsistency persists, the aggregation will fail
again. The aggregation will only succeed when VLAN information is consistent and
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