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Partial Network Outage on Catalyst WS-C6509-E using dual Sup

Dear expert,

I have problem experiencing partial network outages in my one Catalyst 6509-E. It happens many times in almost 2 months, and when it happens partial network outage takes about 10 minutes (LAN and WAN traffic down).

I have a suspect that something is not right for the dual supervisor redundancy (when doing switchover). I also noticed that the standby Sup in slot 6 shows 'Minor Error'. I went to the 'Error Message Decoder' at to interpret the error messages from the log, but it says: no action is required. For details i enclose the log from the switch.

Please Advice to resolve this problem.

Thank You in Advance


Note: I use IOS s72033-ipservicesk9_wan-mz.122-18.SXF9.bin and dual Sup WS-SUP720-3B


Re: Partial Network Outage on Catalyst WS-C6509-E using dual Sup

Traffic outage is seen for a few seconds with LACP channels. This condition is seen with default values of MVRP timers and when the number of VLANs is greater than1500. When a new port is added or deleted, the load value is reset on all the ports. A new load is then distributed on all the ports in the Cisco EtherChannel interface, including the new member, and reprogrammed into the port ASIC for each port. This process causes packets to be dropped during the short outage window (approximately 200 to 300 ms), an undesirable result for higher-speed interfaces such as 10 Gigabit Ethernet connections where a large amount of traffic may be lost during this brief outage window.

For further information click this link.

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