5 replies to this topic

[loverzizo]

hello for all
i bought cisco asa 5540
i have cisco router 2811 with static ip
84.219.22.96/30
and make nat to conected to internet pat nat
and have
84.219.22.80/29 for exchange server

i want to confiure asa behind router
i mean leave all configure on cisco router
when i make out side and inside lan all is ok
but all pc conected on inside interface of asa 5540 cannot access to internet
and also cannot ping from pc ip on interface outside i permet icmp in servise poilcy and incpection icmp
but i mean no conection not ping only
my senaro
lan------------------ asa -------------------- cisco router ----------internet

i will post configration for asa
ASA Version 8.4(2)
!
hostname ciscoasa
enable password 8Ry2YjIyt7RRXU24 encrypted
passwd 2KFQnbNIdI.2KYOU encrypted
names
!
interface GigabitEthernet0/0
nameif outside
security-level 0
ip address 192.168.193.3 255.255.255.0
!
interface GigabitEthernet0/1
nameif inside
security-level 100
ip address 192.168.191.1 255.255.255.0
!
interface GigabitEthernet0/2
shutdown
no nameif
no security-level
no ip address
!
interface GigabitEthernet0/3
shutdown
no nameif
no security-level
no ip address
!
interface Management0/0
nameif management
security-level 100
ip address 192.168.1.1 255.255.255.0
management-only
!
ftp mode passive
same-security-traffic permit inter-interface
same-security-traffic permit intra-interface
access-list OUTSIDE extended permit ip any any
access-list inside_access_in extended permit icmp any interface outside
access-list cap extended permit icmp any host 4.2.2.2
access-list cap extended permit icmp host 4.2.2.2 any
pager lines 24
logging asdm informational
mtu outside 1500
mtu inside 1500
mtu management 1500
no failover
icmp unreachable rate-limit 1 burst-size 1
no asdm history enable
arp timeout 14400
access-group OUTSIDE in interface outside
access-group inside_access_in in interface inside
route outside 0.0.0.0 0.0.0.0 192.168.193.2 1

timeout tcp-proxy-reassembly 0:01:00
timeout floating-conn 0:00:00
dynamic-access-policy-record DfltAccessPolicy
user-identity default-domain LOCAL
http server enable
http 192.168.1.0 255.255.255.0 management
no snmp-server location
no snmp-server contact
snmp-server enable traps snmp authentication linkup linkdown coldstart
telnet timeout 5
ssh timeout 5
console timeout 0

!
threat-detection basic-threat
threat-detection statistics access-list
no threat-detection statistics tcp-intercept
webvpn
username admin password .Yb5gwK7xqjZkYI4 encrypted privilege 15
!
class-map inspection_default
match default-inspection-traffic
!
!
policy-map type inspect dns preset_dns_map
parameters
message-length maximum client auto
message-length maximum 512
policy-map global_policy
class inspection_default
inspect dns preset_dns_map
inspect ftp
inspect h323 h225
inspect h323 ras
inspect rsh
inspect rtsp
inspect esmtp
inspect sqlnet
inspect skinny
inspect sunrpc
inspect xdmcp
inspect sip
inspect netbios
inspect tftp
inspect ip-options
inspect icmp
inspect icmp error
!
service-policy global_policy global
prompt hostname context
: end
my router access to internet and all lan access to intenet without asa
so what is missing or wrong conigration to access to internet
best regards

[MarkinManchester]

Can you not configure it as a transparent firewall? Just use ASDM and avoid the headache of configuring it via the CLI.

[Yorel]

Hello

The only traffic you allow from the LAN to outside is ping to outside interface, because of it the users cannot access internet.

By the other hand, asa drops any icmp that go through itself. PCs only can do ping to inside interface, neither osutide nor dmz or other interface. Finally, you will need to do nat on asa if the router doesnt.

Regards

[loverzizo]

i have nat on cisso router
so i dont need it
and i make access-list to permit all
not icmp only
and no internet access
no http access
no icmp access

[Yorel]

Try packet-tracer input in order to simulate a packet from the LAN to internet, so you will know if ASA is droping the connection or not. See this link:

http://www.cisco.com...080734db7.shtml

[nikm]

In your config:

access-list OUTSIDE extended permit ip any any
access-list inside_access_in extended permit icmp any interface outside
... ...
access-group OUTSIDE in interface outside
access-group inside_access_in in interface inside

You are permitting all traffic from the internet to come in (permit ip any any on the outside interface in inbound direction) and you are denying all traffic from the inside network out except pings to the outside interface of the firewall.

You probably intended to do the opposite, i.e. allow inside users all access to internet and permit external pings to firewall.
You can do the first with:

access-list inside_access_in extended permit permit ip any any
access-group inside_access_in in interface inside

This however is also the default set up, as the firewall will permit traffic from a higher security interface to any lower security interface. So no access list is necessary unless you need something more specific.

To allow ping s to the fiorewall you need to use the icmp command, like in:

icmp permit any echo outside

This will permit any host to ping the firewall on the outside interface. ICMP permissions applied through access lists apply only to thraffic going through the firewall, not destined to the firewall itself.