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Traffic on VLAN 1 - Processed switched

I know certain protocols hit SUP mod's CPU, however if VLAN traffic is configured on VLAN1 does this also hit the CPU and get "processed switched".

I know certain protocols such as IGMP etc always hit CPU according to some tests we have done.

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Re: Traffic on VLAN 1 - Processed switched

It doesn't really matter what VLAN the traffic is on, just the amount of it and the switching method. Process switching is the most CPU intensive form of switching.

What hardware are you using?


Re: Traffic on VLAN 1 - Processed switched

Hi Daniel,

It's a 65xx, however the architecture of the switch and the way the code handles certain protocols is hard to get out of Cisco.

I just remember there are limitations with VLAN 1 in terms of CPU etc, hence the reason to keep all user traffic of that VLAN, and i have read somewhere that all traffic is destined for port 0 when "VLAN 1 tagged"

Seeming that all management traffic such as VTP, DRiP, CDP etc are processed by CPU and some other multicast traffic is also CPU processed. There is also two modes the bus on a 6500 operates in and i can not find which one VLAN1 uses.

Basically this causes a full interupt on CPU which is undesired, i was asking if all traffic on VLAN 1 is destined for CPU processing, i know Traffic on other VLAN's are switched by either CAM or TCAM, or more recently L3 and CEF (MLS).



There is a logical port 0 on the SUP and i would like to find out if all VLAN1 traffic gets processed by that port. :)

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