Re: any icmp access-list mistake....

in simple words

router generated traffic will not be filtered by the " outbound " acl
is this , you all are saying ?

On Thu, Oct 4, 2012 at 6:30 PM, marc edwards <renorider_at_gmail.com> wrote:

> Bobola,
>
> Good point.... So long as ACL is ingress on interface facing R2 the
> traffic can be choked before it hits the loopback.
>
> 2 solutions to the same problem (unless there are added restrictions
> one way or the other....).
>
> On Thu, Oct 4, 2012 at 3:44 AM, Bobola Oke <okebobola_at_gmail.com> wrote:
> > Hello,
> >
> > If you try applying the acl inbound, that should work.
> >
> >
> >
> >
> > On Mon, Oct 1, 2012 at 7:40 PM, marc edwards <renorider_at_gmail.com>
> wrote:
> >>
> >> NP. In summary, through the router (data) can be blocked at interface.
> To
> >> the router traffic (control) is blocked with CoPP
> >>
> >> Marc
> >>
> >> On Mon, Oct 1, 2012 at 11:36 AM, ccie99999 <ccie99999_at_gmail.com> wrote:
> >>
> >> > OMG.. I know that was easy.. I was confused. Sorry.
> >> >
> >> > @ccie99999
> >> > Il giorno 01/ott/2012 18:11, "marc edwards" <renorider_at_gmail.com> ha
> >> > scritto:
> >> >
> >> > So the ping from R2 through R1 to R3 is blocked becuase the ACL you
> >> >> applied on router 1 is for data forwarding.
> >> >>
> >> >> When you ping loopback of the router, it is control-plane traffic.
> >> >>
> >> >> You can apply CoPP if you want to stop this type of traffic.
> >> >>
> >> >> On R1:
> >> >>
> >> >> !
> >> >> ip access-list extended R1-loop-back
> >> >> permit icmp host 1.1.1.1 any echo-reply
> >> >>
> >> >> !
> >> >> class-map match-all control-ping
> >> >> match access-group name R1-loop-back
> >> >> !
> >> >> policy-map control-ping
> >> >> class control-ping
> >> >> drop
> >> >> !
> >> >> control-plane
> >> >> service-policy output control-ping
> >> >>
> >> >> HTH
> >> >>
> >> >> Marc
> >> >>
> >> >> On Mon, Oct 1, 2012 at 5:25 AM, ccie99999 <ccie99999_at_gmail.com>
> wrote:
> >> >>
> >> >>> Well, I did lab that and I'm confused.
> >> >>>
> >> >>> I have the same behaviour.
> >> >>>
> >> >>> R3 - R1 - R2
> >> >>>
> >> >>> from R2 I ping R1's L0 and I got replies.
> >> >>> from R3 I ping R3's L0 and I don't get replies.
> >> >>>
> >> >>> R1's Loop0 is 1.1.1.1/24
> >> >>> R3's Loop0 is 1.1.3.1/24
> >> >>>
> >> >>> access-list applied to R1 fa0/0 (side R2) is this one:
> >> >>>
> >> >>> Extended IP access list LOOP
> >> >>> 10 deny icmp 1.1.0.0 0.0.255.255 any echo-reply (10 matches)
> >> >>> 20 permit ip any any
> >> >>>
> >> >>> I've setup 'no ip unreachable' on R1's Loop0 but as far as I get a
> >> >>> reply
> >> >>> I
> >> >>> guess this doesn't apply..
> >> >>> or am I missing something?
> >> >>>
> >> >>> R2#ping 1.1.1.1 rep 2
> >> >>>
> >> >>> Type escape sequence to abort.
> >> >>> Sending 2, 100-byte ICMP Echos to 1.1.1.1, timeout is 2 seconds:
> >> >>> !!
> >> >>>
> >> >>> R2#ping 1.1.3.1 rep 2
> >> >>>
> >> >>> Sending 2, 100-byte ICMP Echos to 1.1.3.1, timeout is 2 seconds:
> >> >>> ..
> >> >>> Success rate is 0 percent (0/2)
> >> >>>
> >> >>>
> >> >>>
> >> >>> thanks
> >> >>>
> >> >>>
> >> >>>
> >> >>> On Mon, Oct 1, 2012 at 9:44 AM, Joseph L. Brunner
> >> >>> <joe_at_affirmedsystems.com>wrote:
> >> >>>
> >> >>> > This is a often overlooked feature - ip unreachables! So even
> though
> >> >>> the
> >> >>> > router will block your pings from being sent when leaving g0/14 -
> >> >>> > its
> >> >>> > giving you a little hint to STOP SENDING THEM!
> >> >>> >
> >> >>> > On the loopback interface -
> >> >>> >
> >> >>> > int loop0
> >> >>> > !
> >> >>> > no ip unreachables
> >> >>> > !
> >> >>> >
> >> >>> > I suggest you read this useful link on securing IOS routers -
> >> >>> >
> >> >>> >
> >> >>> >
> >> >>>
> >> >>>
> http://www.cisco.com/en/US/tech/tk648/tk361/technologies_tech_note09186a0080120f48.shtml
> >> >>> >
> >> >>> > and this timeless whitepaper - which is a great use of our tax
> money
> >> >>> :0)
> >> >>> >
> >> >>> > http://www.nsa.gov/ia/_files/routers/C4-040R-02.pdf
> >> >>> >
> >> >>> >
> >> >>> > :)
> >> >>> >
> >> >>> >
> >> >>> > -----Original Message-----
> >> >>> > From: nobody_at_groupstudy.com [mailto:nobody_at_groupstudy.com] On
> Behalf
> >> >>> Of
> >> >>> > muhammad adnan
> >> >>> > Sent: Monday, October 01, 2012 5:29 AM
> >> >>> > To: Cisco certification
> >> >>> > Subject: any icmp access-list mistake....
> >> >>> >
> >> >>> > Dear all group members:-
> >> >>> >
> >> >>> > i am doing small testing. i want to block all ping from my pc
> >> >>> > attached
> >> >>> at
> >> >>> > gi0/14 to 192.168.x.0 255.255.255.0
> >> >>> >
> >> >>> > when i applied the access-list stated below ping reply block from
> >> >>> > all
> >> >>> > address 192.168.x.0 255.255.255.0 instead of
> 192.168.x.1.192.168.x.1
> >> >>> > is
> >> >>> > directly connected to my switch but the rest of loopback address
> are
> >> >>> > 1
> >> >>> hop
> >> >>> > away.
> >> >>> >
> >> >>> >
> >> >>> > i already clear cef and arp cache.
> >> >>> >
> >> >>> >
> >> >>> > and i am unable to found a stupid mistake or any reason why
> >> >>> > 192.168.x.1
> >> >>> > give me echo reply
> >> >>> >
> >> >>> > any idea....
> >> >>> >
> >> >>> >
> >> >>> >
> >> >>> >
> >> >>> >
> >> >>> > interface Loopback0
> >> >>> > ip address 192.168.x.1 255.255.255.255
> >> >>> >
> >> >>> > interface GigabitEthernet0/14
> >> >>> > description ......
> >> >>> > no switchport
> >> >>> > ip address x.x.x.x 255.255.255.252
> >> >>> > ip access-group loop-back out
> >> >>> >
> >> >>> >
> >> >>> >
> >> >>> >
> >> >>> > ip access-list extended loop-back
> >> >>> > deny icmp host 192.168.x.1 any echo-reply
> >> >>> > deny icmp 192.168.x.0 0.0.0.255 any echo-reply
> >> >>> > permit ip any any
> >> >>> >
> >> >>> >
> >> >>> > Blogs and organic groups at http://www.ccie.net
> >> >>> >
> >> >>> >
> >> >>> >
> _______________________________________________________________________
> >> >>> > Subscription information may be found at:
> >> >>> > http://www.groupstudy.com/list/CCIELab.html
> >> >>> >
> >> >>> >
> >> >>> > Blogs and organic groups at http://www.ccie.net
> >> >>> >
> >> >>> >
> >> >>> >
> _______________________________________________________________________
> >> >>> > Subscription information may be found at:
> >> >>> > http://www.groupstudy.com/list/CCIELab.html
> >> >>> >
> >> >>> >
> >> >>> >
> >> >>> >
> >> >>> >
> >> >>> >
> >> >>> >
> >> >>> >
> >> >>>
> >> >>>
> >> >>> --
> >> >>> @ccie99999
> >> >>>
> >> >>>
> >> >>> Blogs and organic groups at http://www.ccie.net
> >> >>>
> >> >>>
> >> >>>
> _______________________________________________________________________
> >> >>> Subscription information may be found at:
> >> >>> http://www.groupstudy.com/list/CCIELab.html
> >>
> >>
> >> Blogs and organic groups at http://www.ccie.net
> >>
> >> _______________________________________________________________________
> >> Subscription information may be found at:
> >> http://www.groupstudy.com/list/CCIELab.html
>
>
> Blogs and organic groups at http://www.ccie.net
>
> _______________________________________________________________________
> Subscription information may be found at:
> http://www.groupstudy.com/list/CCIELab.html

Blogs and organic groups at http://www.ccie.net
Received on Thu Oct 04 2012 - 19:41:23 ART