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Community Member

Strange CPPr Behaviour

Hi All,

I try to play with CPPr and I came with the following to drop all packets to closed ports except RIP:

class-map type port-filter match-all closed

match  closed-ports

class-map type port-filter match-any validPorts

match  port udp 520

policy-map type port-filter PortPMAP

class validPorts


class closed


control-plane host

service-policy type port-filter input PortPMAP

and that works fine, now, if I remove the log action of validPorts, I stop receiving RIP updates (checked with debug ip RIP) and my routes eventually become removed on routing table.

Per this link:

policy-map copp-policy

class coppclass-bgp

< no operation specified since this class has unrestricted access to route processor >

So I would expect that even with no log my traffic should be permitted.

Is this a bug, or did I missed something ?

I am running on

R3(config)#do sh ver  | i IO

Cisco IOS Software, 2800 Software (C2800NM-ADVENTERPRISEK9-M), Version 15.1(3)T2, RELEASE SOFTWARE (fc1)


Strange CPPr Behaviour

I think you're running into this problem because RIP uses brodcasts. Try enabling RIPv2 and specifiying a neighbor. That will enable RIP to use multicast. This would need to be done on each router.

Hope it helps.

Community Member

Strange CPPr Behaviour

Hi Collin,

I already have RIPv2. When I have the log action, I see packets to, it's just for some reason if I do not put a log action packets looks droppped.

As a workaround I can do

class-map type port-filter match-all closed

match  closed-ports

match not udp 520

But that is strange... Maybe i'll try a differnet IOS version if I have some time.

Strange CPPr Behaviour

I can try it in the lab tonight too.

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