Hi Jimmy,

ZBF is always a sticky topic.

Here is my run down:

the ICMP is going to be Stateful so you know it needs to be inspected.  Try
the following:

ip access-list extended acl-INSIDE-TO-OUTSIDE-no-inspect
 permit icmp any any eq echo

class-map type inspect class-INSIDE-TO-OUTSIDE-no-inspect
 match access-group acl-INSIDE-TO-OUTSIDE-no-inspect

policy-map type inspect policy-INSIDE-TO-OUTSIDE
 class type inspect class-INSIDE-TO-OUTSIDE
  inspect

! Next the ICMP- it actually does need to be inspected to allow for the
reply.

class type inspect class-INSIDE-TO-OUTSIDE-no-inspect
 inspect
 class class-default
  drop


You don't do any interfaces ACLs, rather they are handled my the class-maps,
in other words you nest them in the policy-map.

Here is a basic post I did on the ZBF.  There is another one coming but I'm
a bit behind.  Hopefully this gives you a push in the right direction.

Also- take a look at the DSG for Lab 2a.  Task 2.11 has ICMP allowed in the
ZBF configuration.  Perhaps that will help a bit.

Regards,

Brandon Carroll - CCIE #23837
Senior Technical Instructor - IPexpert
Mailto: [email protected]
Telephone: +1.810.326.1444
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On Wed, Feb 3, 2010 at 12:54 PM, Jimmy Larsson <[email protected]> wrote:

>
> Hi
>
> I am trying some zone based firewall configurations am getting confused. My
> background is that I am very familiar with Pix/ASA and not very familiar at
> all with the Firewall-features of IOS. Therefore I always compare these
> which gets me confused.
>
> Now I´ve done a simple 2-zone firewall out of my 3-legged router. My goal
> is this:
> * Allow all outbound telnet stateful
> * Allow all icmp-echos initiated from inside (and ofcourse the
> corresponding echo replies)
> * Deny everything else between the zones.
>
> I have configured the two zones and a policy-map that inspects and allows
> my outbound telnet. It looks like this:
>
>
>
> class-map type inspect match-any class-INSIDE-TO-OUTSIDE
>  match protocol telnet
> !
> !
> policy-map type inspect policy-INSIDE-TO-OUTSIDE
>  class type inspect class-INSIDE-TO-OUTSIDE
>   inspect
>  class class-default
>   drop
> !
> zone security OUTSIDE
> zone security INSIDE
> zone-pair security INSIDE-TO-OUTSIDE source INSIDE destination OUTSIDE
>  service-policy type inspect policy-INSIDE-TO-OUTSIDE
>
>
> interface FastEthernet0
>  description Outside
>  zone-member security OUTSIDE
> !
> interface FastEthernet1
>  description Inside
>  zone-member security INSIDE
> !
> interface Vlan13
>  zone-member security INSIDE
> !
>
> So, now I can telnet from outside to telnet. But what about the icmp:s? My
> idea was to create a class-map referring to an acl that defines non-stateful
> outbound-traffic that should be allowed. Something like this:
>
> ip access-list extended acl-INSIDE-TO-OUTSIDE-no-inspect
>  permit icmp any any eq echo
>
> class-map class-INSIDE-TO-OUTSIDE-no-inspect
>  match access-group acl-INSIDE-TO-OUTSIDE-no-inspect
>
> But when trying to apply this to my policy-map (my goal was to do
> "pass"-action on this) I get this error:
> r1(config-pmap)#class class-INSIDE-TO-OUTSIDE-no-inspect
> % class class-INSIDE-TO-OUTSIDE-no-inspect of type default is not allowed
> in policy-map policy-INSIDE-TO-OUTSIDE of type inspect
>
> In what way am I thinking wrong here?
>
> Also, in my scenario, how should my interface acl:s look like when doing
> this zone-thing? Since traffic between zones are blocked by default and
> traffic inside a zone is permitted, I guess that I should´nt have any
> interface acl:s since all transit traffic security is taken care of by the
> zone-configuration. Right? Can there be any situation where interface acl:s
> are needed when doing ZBFW?
>
> Thanks in advance!
> --
> -------
> Jimmy Larsson
> Ryavagen 173
> s-26030 Vallakra
> Sweden
> http://blogg.kvistofta.nu
> -------
>
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>
>
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