Hi kings,

What if you enable cef globally but disable on an ingress interface?

Pj

Sent from an iPhone

Op 15 nov. 2010 om 15:33 heeft Kingsley Charles <[email protected]> 
het volgende geschreven:

> Hi PJ 
> 
> CPPr requires cef, if you disable cef, all the three CPPr sub-interfaces are 
> disabled and you will see the the following message on the console:
> 
> On contrast CoPP can work without CEF. 
> 
> I am looking for a feature or traffic that uses process switch with CEF 
> enabled on the router.
> 
> router2(config)#no ip cef
> router2(config)#
> Nov 13 12:17:09.667: %CP-4-CPPR_DISABLED: Removing security features on host, 
> tr
> ansit and cef-exception paths
> router2(config)#
> router2(config)#
> Nov 13 12:17:09.667: %CP-5-FEATURE: Control-plane Policing feature disabled 
> from
>  Control plane host path
> 
> Nov 13 12:17:09.667: %CP-5-FEATURE: Control-plane Policing feature disabled 
> from
>  Control plane transit path
> 
> Nov 13 12:17:09.667: %CP-5-FEATURE: Control-plane Policing feature disabled 
> from
>  Control plane cef-exception path
> 
> 
> With regards
> Kings
> 
> On Mon, Nov 15, 2010 at 2:05 PM, Pieter-Jan Nefkens 
> <[email protected]> wrote:
> Hi kings,
> 
> You can disable cef completely by using global config (issue 3)
> 
> No ip cef
> 
> You can also use it on interfaces do disable the hardware entries
> No ip route-cache flow
> 
> Hth
> 
> Pj
> 
> 
> Sent from my iPad
> 
> On 15 nov. 2010, at 08:59, Kingsley Charles <[email protected]> 
> wrote:
> 
>> Hi all
>> 
>> I am trying to block fragmented packets to control plane (both CoPP & CPPr). 
>> Adding one more issue.
>> 
>> Issue 1
>> 
>>     I wanted to simulate fragmented session.
>> 
>>     Let me admit that using ICMP to test CPPr host sub-interface doesn't 
>> seem to be the right way. You need to test with TCP or UDP applications as 
>> CPPr only handles TCP and UDP traffic.
>> 
>>  
>> 
>>     And the other thing I observed is that fragmented ICMP packets doesn't 
>> come into CoPP and is just allowed
>> 
>>     So I tried copying a file of size 2250 KB using ftp, tftp and also 
>> viewed a running config greater 2000 Bytes of another router from my router 
>> that was configured for control plane.
>> 
>>     But none of them seem to be generating fragmented packets.
>> 
>>     I tried configuring the following ACL on the receiving interface to see 
>> for fragmented packets but I didn't see the counters increasing for first 
>> ACE with frag keyword
>> 
>>     access-list 123 permit ip any any fragments
>>     access-list 123 permit ip any any
>> 
>>     Is there something wrong in the way of my simulation for generating 
>> fragmented packets for ftp, tftp and telnet?
>> 
>> 
>> Issue 2
>> 
>>     To get the simulation work, I launched the home page of the router using 
>> a browser and in that I used the extended Ping utility. I self pinged with 
>> size of 2000 bytes and I was able to see the results. The Pings are sent 
>> through HTTP and HTTP which is TCP application is being fragmented. Hence, I 
>> get a simulated fragmented TCP packets to the control plane.
>> 
>> 
>>     class-map match-all frag
>>      match access-group 123
>> 
>>     policy-map frag
>>      class frag
>>        drop
>> 
>> 
>>     access-list 123 permit ip any any fragments
>> 
>>     If I apply the policy to CoPP, it works. The fragmented packets are 
>> getting dropped.
>> 
>>     control-plane
>>     service-policy input frag
>> 
>> 
>>      If I apply the policy to CPPr host sub-interface. The fragmented 
>> packets are not getting dropped rather all the fragmented packets are 
>> classified in  the  default class which means control plane host doesn't 
>> match fragmented packets.
>> 
>>      control-plane host
>>      service-policy input frag
>> 
>>      router2#sh policy-map control-plane host
>>  Control Plane Host
>> 
>>   Service-policy input: frag
>> 
>>     Class-map: frag (match-all)
>>       0 packets, 0 bytes
>>       5 minute offered rate 0 bps, drop rate 0 bps
>>       Match: access-group 123
>>       drop
>> 
>>     Class-map: class-default (match-any)
>>       127 packets, 13237 bytes
>>       5 minute offered rate 0 bps, drop rate 0 bps
>>       Match: any
>>    
>>    Why isn't control plane host sub-interface handle fragmented packets?
>> 
>> 
>> Issue 3
>> 
>> I am trying block fragmented packets using transit plane.
>> 
>> The transit sub-interface only deals with process switched traffic. Hence I 
>> put a router behind the router configured for the control transit plane and 
>> cleared the arp-cache. Now I tried to ping that router which is behind and 
>> since there is no ARP cache, thereby do CEF table populated, the router 
>> configured for control plane process switches the Ping and hence, I get a 
>> simulated process switched ping. 
>> 
>> But I am not able to continue with this process switched ping with 
>> fragmented packets as there is no ARP. Once I configure ARP manually, the 
>> CEF table is built and fragmented packets are CEF switched, thereby permitted
>> 
>> Can someone tell me a way to test fragmented process switch traffic across 
>> the transit sub-interface.
>> 
>> 
>> 
>> 
>> 
>> With regards
>> Kings
>> _______________________________________________
>> For more information regarding industry leading CCIE Lab training, please 
>> visit www.ipexpert.com
> 
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