Hi @Cisconewbie1
Very simple topology wiould look like:
Switch g0/1 --- g0/0 Router g0/1 ---E0/0 ASA E0/1--- ISP
So let's get into configuration.
ASA:
Configuration commands might change depending on what version your fw is running. The below config is for 8.3 version.
First configure your inside interface plugged to router:
interface E0/0
nameif inside
security-level 100
ip address 192.168.0.1 255.255.255.252
!
Here I put static public IP for the outside interface facing ISP.
interface E0/1
nameif outside
security-level 0
ip address 1.1.1.1 255.255.255.252
!
PAT configuration which is allowing all internal subnets coming from your LAN.
global (outside) 1 interface
nat (inside) 1 0.0.0.0 0.0.0.0
!
Then we'll need default static route to the outside world.
route outside 0.0.0.0 0.0.0.0 1.1.1.2 1
Static route to internal LAN
route inside 192.168.10.0 255.255.255.0 192.168.0.2 1
!
That's minimum required config on ASA you might tune it for your needs.
Router:
Here very basic router on a stick configuration.
int g0/1
desc ASA
ip add 192.168.0.2 255.255.255.252
no sh
!
int g0/0
no sh
no ip add
!
int g0/0.10
desc LAN, VLAN 10
encapsulation dot1q 10
ip add 192.168.10.1 255.255.255.0
no shut
!
ip route 0.0.0.0 0.0.0.0 192.168.0.1
!
Assuming your internal users are in VLAN #10.
Switch:
All your switch needs is correct VLAN mapping on access ports and trunk port facing router.
vlan 10
name LAN
!
int g0/1
desc Router
swtichport mode trunk
switchport trunk encapsulation dot1q
!
int g0/2
switchport mode access
switchport access vlan 10
spanning-tree portfast
!
For other users connected port config will be the same like for g0/2.
That's absolute minimum configuration piece. Other stuff you might also add are - SSH, Syslog, SNMP, ACLs etc.
Best regards,
Abzal
