netflow showing inbound traffic only

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I have enabled netflow on a Cisco 1800 router. All the interfaces are showing inbound and outbound traffic apart from Fastethernet 0. It is showing Traffic for inbound only.

when I run show ip flow interface, I noticed that it created a subinterface for fastethernet0 even though I did not create it manually. Also sh ip cache flow is reporting traffic to be Local (not sure if this is of any relevance)

Some output:

ittcrt03-perurt01#sh ip cache flow | inc Fa

Fa0 Local 2F 0000 0000 1

Fa0 Local 2F 0000 0000 145

Fa0 Local 2F 0000 0000 2


ittcrt03-perurt01#sh ip flow interface


ip route-cache flow

ip flow ingress

ip flow egress


ip flow ingress

ip flow egress



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Jan Nejman Wed, 02/13/2008 - 08:37
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I recommend not using 'ip flow egress' and using 'ip flow ingress' on all interfaces on your router. Using netflow on egress is used only for several special cases, but normal configuration is 'ip route-cache flow' (deprecated command) or 'ip flow ingess' on all L3 interfaces. Do you using NAT?

Kind regards,

Jan Nejman

Caligare, Co.

Jan Nejman Fri, 02/15/2008 - 07:55
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did you enable 'ip flow ingess' on all interfaces? i.e Fast 0/1, 0/2 ... Could you send me output of the:

show ip interface brief

show runn | inc flow

Kind regards,



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