Hello,
I encountered an issue with output discards on 1G interfaces during micro bursts from 10G uplinks.
In my case i think i need to make a more efficient buffer allocation on problem interfaces.
I have read an article and something is not clear for me.
http://www.cisco.com/c/en/us/support/docs/switches/catalyst-3850-series-switches/200594-Catalyst-3850-Troubleshooting-Output-dr.html
Could anyone please give a more detailed explanation to:
"There is no Hardmax buffer since the policy is applied to an interface and it does not have any priority queue with "level" set.
As soon as you apply the policy-map, the 2nd queue gets disabled leaving only 1 queue in the system.
The caveat here is that all packets are going to use this single queue (including the control packets like OSPF/EIGRP/STP).
During the time of congestion (broadcast storm etc), this may easily cause network disruption.
This is true if you have other classes defined but not matching the control packets."
And . . .
." If you define only 1 class-default, in order to tweak the buffer, all the traffic falls under the single queue (including control packets). Be advised that when all traffic is put in one queue, there is no classification between control and data traffic and during time of congestion, control traffic could get dropped. So, it is recommended to create at least 1 other class for control traffic. CPU generated control-packets will always go to the first priority queue even if not matched in the class-map. If there is no priority queue configured, it would go to the first queue of the interface, which is queue-0."
In my case i need to make two queues:
1. For control plane traffic
2. For all data plane traffic (MAX hard and soft buffers)
How i can characterize control plane traffic for a specific queue?
Do i need it at all?
Thank you.
