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Recommendations on Rx queue settings


On C6500, Cisco seem to rarely give recommended settings for Rx, only for Tx.

I think this is because they say Rx congestion rarely occurs.

For the sake of this discussion I'd like to assume it can occur (which has some basis in fact when you consider eg. 6148A is 8:1 oversubscribed, ie. 8 external 1G ports converge on one 1G bus internal to this Line Module.)

1) Does the Rx WRED start acting when there is congestion of the bus internal to the Line Module?

2) Does the Rx WRED start acting when there is congestion of Sup32 bus?

regards, MH


Re: Recommendations on Rx queue settings

I have heard that Cisco switches have a minimum support to handle sudden burst of traffic. The port receiving the sudden burst of traffic will be given some extra access to the bus than the other ports. But this works only for some period of time. After that the switch will start dropping the frames. If your are receiving heavy inflow frequently, then you have to look at the network design.