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I need to DMZ access to internet and see the inside on ASA 5520

Hi everyone.

I am new in ASA, I have the DMZ ( configured on ASA 5520 and I achieve the reach Internet from DMZ (, but now need reach DMZ from inside ( and inside ( from DMZ  (, in other words round trip.

ths show run is attached.

I try with the next links, but dont work.

thk for help me !!!


6 Replies 6

Marvin Rhoads
VIP Community Legend VIP Community Legend
VIP Community Legend

Since the DMZ is lower security level than inside, you must create and apply and access-list to allow DMZ-originated traffic to access inside addresses.

Something like:

access-list DMZ_IN extended permit

access-group DMZ_IN in interface DMZ

Inside to DMZ will automatically work (unless you start ACLing in in which case an implicit deny will be added at the end).

If you're new to the ASA, I recommend you use ASDM to create your changes. Set it to preview commands and look at what it generates to understand the CLI.

hi Marvin.

I try with ASDM but I do not like, I think that is better with CLI.

I try with you tell me later, i think that this help me.

access-list DMZ_IN permit
access-list DMZ_IN permit

access-group DMZ_IN permit in interface DMZ

static (inside,DMZ) netmask

you tihink that this help me?

BR and THK!!!

Yes, what you have proposed looks good.

ok, let me try out production and update you.


Hi Marvin,

Apologies for the delay but too much work here, I try with the next command.

access-list DMZ_IN extended permit tcp

access-list DMZ_IN extended permit udp

access-list DMZ_IN extended permit tcp

access-list DMZ_IN extended permit udp

access-group DMZ_IN in interface DMZ

nat (DMZ) 1

static (inside,DMZ) netmask

and when I configure the PC with DGW (interface DMZ`s firewall) I don't reach the LAN but Internet is reachable, i need to reach both (LAN-, and Internet).

do you have someone idea for help me?

thk so much!!!

Try using packet-tracer on the ASA to follow the logic through the box and determine why your DMZ-Inside traffic isn't working.

packet-tracer input dmz detailed

The output should tell you why the packets aren't flowing.

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