For some reason, this week I’ve been bombarded with questions regarding configuring the 6509 Catalyst for NetFlow.

Being a switch/router hybrid model, the configurations are a little different from standard CISCO routers models, like the 2811, but not too much.

I would also recommend checking out this great resource directly from CISCO to configure the 6509 Catalyst for NetFlow.

With most CISCO routers, there are two sets of commands used to enable NetFlow. However, with the 6509, there are technically three sets of commands.

To enable NetFlow on the router, you need the following:

ip flow-export source (insert interface name here)
ip flow-export version 5
ip flow-export destination (netflow collector ip address) (port to export flows to)
ip flow ingress layer2-switched vlan (insert vlans X,Y,X)

ip flow-cache timeout active 1

Once those are in place, we now need to configure NetFlow for the switched traffic:

mls nde sender version 5
mls flow ip interface-full
mls nde interface
mls aging long 64
mls aging normal 64

After you have configured these globals, you now can configure each of the interfaces themselves for NetFlow:

ip route-cache flow


ip flow ingress

I have discussed the usage of the ip route-cache flow and ip flow ingress commands before. You might want to take look for more details.

That wasn’t so bad, was it?

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Ryan Slosser

My name is Ryan. I work in development here at Plixer. I mostly deal with hardware deployment. I enjoy kayaking and fishing during the summer and skiing in the winter. People can count on me and I always give 100% unless I'm donating blood.


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