Network Operators and smurf

barton at barton at
Sat Apr 25 19:55:40 UTC 1998

>Current recipe for anti-forging with Cisco hardware:

> o Pick up CEF code (11.1(17)CC, which doesn't yet (?) exist for all
>   Cisco platforms, unfortunately)

> o Configure:

>   !
>   ip cef switch
>   ! or "ip cef distributed switch" for an RSP+VIP2 based box
>   !
>   interface whatever
>     ip verify unicast reverse-path
>   !

I don't know what exact configs are vulnerable, but don't try this
on a 7206 if you have a PA-8T with frame relay on it.

I had CEF only on PA-2T3 ports and F0/0 on the controller card and yet
all frame relay connections on multiple T1s on the PA-8T were trashed.

cscdj87169 is not resolved yet.

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