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ASA - inside to dmz not working

Unanswered Question
Jun 14th, 2010
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Unable to access DMZ host from inside network

     - can ping inside interace of ASA from inside network

     - can ping dmz interface of ASA from dmz host (test laptop configured with dmz ip address)

     - can ping inside network from ASA

     - can ping dmz network (test laptop) from ASA


     - permit inside hosts access to the dmz network

     - deny dmz network access to inside hosts

No traffic is passing thru from inside to the dmz (to the test laptop)

Confused as to why this configuration isnt working.  Please help.


ASA Version 8.0(4) <context>
hostname lab
interface GigabitEthernet0/0.557
description DMZ lab L2
nameif DMZ
security-level 50
ip address
interface GigabitEthernet0/1.565
description INSIDE lab L3
nameif inside
security-level 100
ip address
object-group service server_maxo_ports tcp
port-object eq www
port-object eq 3389
object-group network server_max
access-list inside_in extended permit ip any any
pager lines 24
mtu DMZ 1500
mtu inside 1500
icmp unreachable rate-limit 1 burst-size 1
no asdm history enable
arp timeout 14400
global (DMZ) 1 interface
nat (inside) 1
static (DMZ,inside) netmask
static (DMZ,inside) netmask
static (DMZ,inside) netmask
access-group inside_in in interface inside
route inside 1
timeout xlate 3:00:00
timeout conn 1:00:00 half-closed 0:10:00 udp 0:02:00 icmp 0:00:02
timeout sunrpc 0:10:00 h323 0:05:00 h225 1:00:00 mgcp 0:05:00 mgcp-pat 0:05:00
timeout sip 0:30:00 sip_media 0:02:00 sip-invite 0:03:00 sip-disconnect 0:02:00
timeout sip-provisional-media 0:02:00 uauth 0:05:00 absolute
no snmp-server location
no snmp-server contact
sysopt noproxyarp inside

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Federico Coto F... Mon, 06/14/2010 - 12:20
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Which IP are you trying to access on the DMZ?

Either enable ICMP inspection or permit ICMP in a new ACL applied to the DMZ and check if you can PING that host from the inside network.

You have these commands:

global (DMZ) 1 interface
nat (inside) 1

So, from the inside you should be able to ''access'' the DMZ network, but please define ''access'' --> which protocol/traffic


tsrader Mon, 06/14/2010 - 12:36
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I had not enabled icmp inspection.  It is done now but still unable to ping dmz host.

policy-map global_policy
class inspection_default
  inspect dns preset_dns_map
  inspect ftp
  inspect h323 h225
  inspect h323 ras
  inspect netbios
  inspect rsh
  inspect rtsp
  inspect skinny 
  inspect esmtp
  inspect sqlnet
  inspect sunrpc
  inspect tftp
  inspect sip 
  inspect xdmcp
  inspect icmp

Note that I am pinging from inside network on different vlan that /27.    As the inside network is fully routed (L3 core switches), the network is considered "directly connected".

From my pc, I am trying to ping (which is dmz host

My ACL is as follows:

access-list inside_in extended permit ip any any
access-list inside_in extended permit icmp any any

Again, from inside network I can ping ASA inside interace.

What am I missing?

Federico Coto F... Mon, 06/14/2010 - 12:42
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You're trying to PING from the inside.
The real IP of the DMZ is but it will be ''seen'' as from the inside.

I have two questions:

Why do you have a default route to the inside?
Do you need to access the DMZ server with an inside IP? (can't you access it with its real IP)?

As a test, I would do a Packet Tracer and see if the ASA reports the connection is torn down somewhere.


tsrader Mon, 06/14/2010 - 12:59
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The DMZ server ip address (10.x.x.x) is non-routable on the inside network hence the reason for static to inside ip address.

Packet tracer results show the following:

Phases 1-8 show ALLOW

Phase: 9
Type: NAT
Subtype: rpf-check
Result: DROP
static (DMZ,inside) netmask
  match ip DMZ host inside any
    static translation to
    translate_hits = 0, untranslate_hits = 0
Additional Information:
Forward Flow based lookup yields rule:
out id=0xcae4e608, priority=5, domain=nat-reverse, deny=false
        hits=0, user_data=0xcb0ab4f0, cs_id=0x0, flags=0x0, protocol=0
        src ip=, mask=, port=0
        dst ip=, mask=, port=0, dscp=0x0

input-interface: inside
input-status: up
input-line-status: up
output-interface: DMZ
output-status: up
output-line-status: up
Action: drop 
Drop-reason: (acl-drop) Flow is denied by configured rule

Federico Coto F... Mon, 06/14/2010 - 13:15
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Just as a test to see if it works, could you add an ACL to the DMZ permitting the traffic?

You're getting acl-drop message, so let's see if by permitting the traffic in an DMZ-ACL it works.

access-list DMZ permit ip any any
access-group DMZ in interface DMZ



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