topic simple ACL confusion in Network Security

simple ACL confusion

J_Vansen_S — Mon, 11 Mar 2019 23:31:40 GMT

Hi All,

I just need to clarify a few simple rule to clear my doubts off.

Apparently i have a outside, inside and DMZ interface.

dmz-server = 172.16.10.10

inside-server = 192.168.1.254'

I just need 2 simple rule.

1. DMZ-server to access inside-server IP only, and deny anything else Inside

2. DMZ-Server to access internet

1. access-list dmz_access_in line 1 extended permit ip object DMZ-Server object INSIDE-SERVER

2. access-list dmz_access_in line 2 extended permit ip object DMZ-Server any

My objective is for DMZ-server to access to only 192.168.1.254, deny to all other inside IP.

Is my above ACL correct? To me, the above 2. ACL seems like overwriting the above rule.

Or am i missing out a DENY rule? if so which order should they be

Please advise.

simple ACL confusion

Jouni Forss — Tue, 17 Jul 2012 09:37:35 GMT

Hi,

Simply configure the following ACL

1. access-list dmz_access_in line 1 extended permit ip object DMZ-Server object INSIDE-SERVER

2. access-list dmz_access_in line 2 extended deny ip object DMZ-Server 192.168.1.0 255.255.255.0

3. access-list dmz_access_in line 3 extended permit ip object DMZ-Server any

Assuming the INSIDE network is 192.168.1.0/24

This will basically do the following

- Allow traffic from the DMZ server to the INSIDE Server

- Block all other traffic from the DMZ -server to the INSIDE network

- Permit all the rest of the traffic from DMZ-server to any other network (for example to all public IP addresses and other LAN networks if you have any)

- Jouni

simple ACL confusion

J_Vansen_S — Tue, 17 Jul 2012 09:39:35 GMT

Thank u very much.!