Oh right. This is local traffic. I keep forgetting that.

Thanks Marc/Steve.

That's a cool way of blocking ospf Steve. Although what would happen if i used 
ip local policy (can't remember the syntax now) with the acl, that would work 
right ?

On Jul 13, 2011, at 6:12 AM, Di Bias, Steve wrote:

> Yup, Marc is spot on in that outbound ACL's don't affect router generated 
> traffic, hence the reason it isn't being filtered. If you did want to filter 
> the routers OSPF traffic (without using passive interface) you can do so by 
> using a policy-map on the control plane like this: 
> 
> R1(config)#router ospf 1
> R1(config-router)# log-adjacency-changes
> R1(config-router)# network 0.0.0.0 255.255.255.255 area 0
> 
> R2(config)#router ospf 2
> R2(config-router)# log-adjacency-changes
> R2(config-router)# netw 0.0.0.0 0.0.0.0 area 0
> 
> 
> *Jul 13 05:09:10.115: %OSPF-5-ADJCHG: Process 2, Nbr 150.10.1.1 on 
> GigabitEthernet0/0 from LOADING to FULL, Loading Done
> 
> 
> R1(config)#ip access extend acl_no_ospf 
> R1(config-ext-nacl)# permit ospf any any
> R1(config-ext-nacl)#!
> R1(config-ext-nacl)#class-map match-all CM_OSPF
> R1(config-cmap)# match access-group name acl_no_ospf
> R1(config-cmap)#!
> R1(config-cmap)#policy-map PM_DROP_OSPF
> R1(config-pmap)#  class CM_OSPF
> R1(config-pmap-c)#   drop 
> R1(config-pmap-c)#!
> R1(config-pmap-c)#control-plane 
> R1(config-cp)# service-policy output PM_DROP_OSPF
> 
> 
> R2(config-router)#
> *Jul 13 05:10:21.067: %OSPF-5-ADJCHG: Process 2, Nbr 150.10.1.1 on 
> GigabitEthernet0/0 from FULL to DOWN, Neighbor Down: Dead timer expired
> 
> Now from this point on R1 will show ip in INIT/DROTHER but the adjacency is 
> pretty much dead
> 
> R2#sh ip ospf neighbor gig0/0
> <neighbor is gone>
> 
> R1(config-cp)#do sh ip o ne fa0/1
> 
> Neighbor ID     Pri   State           Dead Time   Address         Interface
> 150.246.0.2       1   INIT/DROTHER    00:00:31    150.21.21.2     
> FastEthernet0/1
> 
> 
> -----Original Message-----
> From: marc abel [mailto:[email protected]] 
> Sent: Tuesday, July 12, 2011 8:27 PM
> To: Alef
> Cc: Di Bias, Steve; [email protected] IE
> Subject: Re: [OSL | CCIE_RS] allowing ospf in acl
> 
> The reason you don't have to allow OSPF out, is that you actually can't block 
> it outbound with an ACL. Outbound acl's don't block packets generated by the 
> router.
> 
> Check this out. I have configured OSPF between R1 and R2 
> __________________________________
> 
> R2(config)# do show ip ospf nei
> 
> Neighbor ID     Pri   State           Dead Time   Address         Interface
> 1.1.1.1           1   FULL/DR         00:00:35    10.10.10.1      Ethernet0/0
> R2(config)#do show run int e0/0
> Building configuration...
> 
> Current configuration : 91 bytes
> !
> interface Ethernet0/0
> ip address 10.10.10.2 255.255.255.0
> ip access-group 101 out
> end
> 
> R2(config)#do show access-list 101
> Extended IP access list 101
>    10 deny ospf any any
> 
> 
> The neighbor stays up.
> 
> -Marc
> 
> On Tue, Jul 12, 2011 at 5:49 PM, Alef <[email protected]> wrote:
>> Hey Steve,
>> Yes, only ospf. It's a lab from one of the Video on demands, i believe Day 
>> security lab, can't remember what task. I don't have the sim running right 
>> now but the outbound acl permits www, 443 and ssh i think.
>> 
>> I just found it curious that you only need it one way. I guess once the tcp 
>> session is setup all is exchanged forward within that one session from there 
>> on.
>> 
>> Alef
>> 
>> On Jul 12, 2011, at 11:42 PM, Di Bias, Steve wrote:
>> 
>>> That will work, but is OSPF they only thing you want to let in? What does 
>>> the outbound ACL (102) look like? What lab are you working on?
>>> 
>>> Thank you,
>>> 
>>> Steve Di Bias
>>> Network Engineer - Information Systems Valley Health System - Las 
>>> Vegas Office - 702- 369-7594 Cell - 702-241-1801 
>>> [email protected]
>>> 
>>> -----Original Message-----
>>> From: [email protected] 
>>> [mailto:[email protected]] On Behalf Of Alef
>>> Sent: Tuesday, July 12, 2011 2:59 PM
>>> To: [email protected] IE
>>> Subject: [OSL | CCIE_RS] allowing ospf in acl
>>> 
>>> When you have say r1 and r2
>>> and you want to only allow ospf in
>>> 
>>> would applying this on R1 fa0/0 (assuming this is the connecting interface 
>>> to R2) inbound be sufficient?
>>> Extended IP access list 101
>>>    10 permit ospf any any (4826 matches)
>>> 
>>> it seems it is. Do we not need to allow ospf going out as well? In my lab 
>>> R1 has acl 102 outbound defined and there is nothing there about ospf.
>>> 
>>> Regards,
>>> Alef
>>> _______________________________________________
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>>> please visit www.ipexpert.com
>>> 
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>> _______________________________________________
>> For more information regarding industry leading CCIE Lab training, 
>> please visit www.ipexpert.com
>> 
>> Are you a CCNP or CCIE and looking for a job? Check out 
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>> 
> 
> 
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