Question about CEF - Cat65xx - IOS

Hi Dennis,

Yes and no. Yes, by default, your IP ACCOUNTING on the interface cannot see any flow beyond first packet, when IP CEF is enabled. On certain SUP/MSFC combinations with certain level of IOS, you can specify "IP CEF ACCOUNTING ..." command (see options with a "?") to report accounting for the flows. So, try it on your switches...

Good luck,

Mike CCNP, CCDP, CCSP, Cisco Voice, MCSE W2K, MCSE+I, Security+, etc. CCIE R&S (in progress), CCIE Voice (in progress)

------ Headset Adapters for Cisco IP Phones

No. Only first packet in a flow goes through RP. Rest is switched by hardware. Keywords - MLS, RP, SP.

No. All packets switched in hardware - including first in every flow. Exception is some types of traffic are switched in software only.

Regards, Andrey.

Is there a way to make sure that ALL packets are switched in software because it should be possible to count all packets on the SVI with "ip accounting" ?

dennis

Probably. But what do you think will happen to performance?

Andrey.

this what I don't know....so I need also informations to tell our customer if he like to work with "ip accounting" he should disable ip cef But as a result the performance decrease !?! Is this right ?

Dennis

That sounds about right. The fully accounted equivilent is Netflow. There are free netflow analysis tools; I haven't used any so I cannot make any recommendations.

it is not possible to disable CEF on a SUP720

Hi

right now...is it also not possible to disable cef on a cat6509 with native IOS 12.1 E see below... ==================================================== cat6509(config)#no ip cef distri

%Cannot disable CEF on this platform

router03(config)#no ip cef ?

accounting Enable CEF accounting

distributed Distributed Cisco Express Forwarding

linecard CEF linecard commands

load-sharing Load sharing

table Set CEF forwarding table characteristics

traffic-statistics Enable collection of traffic statistics ===========================================

dennis

sorry I forgot...it is a SUP2 with native IOS ...12.1(26)E