Port channel disruption due to one E port down

[vinay.trivedi]

Hi

We have one port channel configured in our Customer environment. This port channel has been configured with 6x4Gbps ports inside it. One of the switch port started flapping (up & down) continuously, which caused multiple alerts on many hosts as well as drastic performance slowness on one of the Business Critical application. It caused a major issue and later on after disabling this port administratively, the issue got resolved.

Could you let me know the cause of major impact and port-channel behavior in such rare cases, where because of one port flapping, whole port channel got affacted ? Is it a expected behavor of port-channel of kind of software bug in Cisco MDS 9513 switches running SAN OS ?

[chris.walden]

Can you share the version of SanOS you are running, as well as the configuration of the port-channel?

[vinay.trivedi]

Hi Chris,

Thanks for the response.

The switch is running with OS version 4.2(7e) and the port-channel  configuration is provided below:

port-channel 31 is trunking   

Admin  port mode is E, trunk mode is on   

snmp link state traps are enabled   

Port mode is TE   

Port vsan is 1   

Speed is 24 Gbps   

Trunk vsans  (admin allowed and active) (1,5,431,435)   

Trunk vsans  (up)                       (1,5,431,435)   

Trunk vsans  (isolated)                 ()   

Member[2] : fc1/2   

Member[3] :  fc1/3   

Member[4] : fc1/4   

Member[5] : fc1/5   

Member[6] : fc1/6

Please let me know in case any further details required.

Regds,

Vinay