CCIE Security Blog

– Don’t forget to enable physical interfaces (e0/0, e0/1, e0/2)
– Create sub-interface and assign VLAN to sub-interface and make sure switch port is in trunking mode. The native (untagged) VLAN of the trunk connection maps to the physical interface, and it cannot be assigned to a sub-interface.

ASA03-5510#interface Ethernet0/3
nameif INSIDE
security-level 0
ip address 136.1.93.17 255.255.255.0

ASA03-5510#interface Ethernet0/0.34
vlan 34
nameif outside
security-level 100
ip address 136.1.34.17 255.255.255.0

ASA03-5510# sh nameif
Interface                       Name                     Security
Ethernet0/0.34           outside                   100
Ethernet0/3                 INSIDE                    0

ASA03-5510# sh ip address
System IP Addresses:
Interface                     Name                   IP address      Subnet mask     Method
Ethernet0/0.34         outside                136.1.34.17     255.255.255.0   manual
Ethernet0/3              INSIDE                136.1.93.17     255.255.255.0   manual
Current IP Addresses:
Interface                    Name                   IP address      Subnet mask     Method
Ethernet0/0.34         outside               136.1.34.17     255.255.255.0   manual
Ethernet0/3              INSIDE               136.1.93.17     255.255.255.0   manual
ASA03-5510#

ASA3# show conn

enable logging on ASA:
#logging on
#logging console 7

– Switch configurations:

interface FastEthernet0/13                      interface FastEthernet0/14
description ASA03 0/3                                   description ASA04 0/3
switchport access vlan 93                              switchport trunk allowed vlan 34
switchport mode access                                 switchport mode trunk
spanning-tree portfast