Interface on asa.

Question

Hi ,
I have connected a firewall inside interface to l3 switch.
on l3 switch
int gi0/1
no switchport
ip address 192.168.10.1 255.255.255.0
no shut    
on firewall
int gi0/1
nameif inside
security level 100
ip address 192.168.10.2 255.255.255.0
If i ping to 192.168.10.2 from firewall thus it ping.
As i know inside host can ping to inside interface.But not any opposite interface such as dmz etc.(need access-list)

Answer 1

Hi Prashant,
Here are two things involved.
1. Ping to the far end interface.
The ASA will not allow to ping the far end interface, for example is you are a host connected on the Inside network and ping the Inside interface the ASA will reply, but if you try to ping the DMZ interface from a host on the inside this will not answer and is expected.
2. Permit traffic from lower to higer interfaces.
All the traffic from higher interface level to lower interface level is permitted by default but is deny the other way around, from lower to higher.
If you need to permit traffic from lower to higher you need to enter a access-list on the lower level interface to permit traffic to the higher security level (If you are on version 8.2 or earlier you might need to add a NAT rule)
For example:
Inside security level 100
Outside security level 0
Inside host 192.168.1.1
access-list outside_access_in permit ip any host 192.168.1.1
access-group outside_access_in in interface outside
http://www.cisco.com/en/US/products/hw/vpndevc/ps2030/products_configuration_example09186a00806745b8.shtml
I hope these helps.
Regards
Godfrey