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Blocking Facebook website with ASA 5510 using fqdn with access-list

godwin osas
Level 1
Level 1

I am trying to block facebook website using fqdn, the problem I am facing is that it block all sites 

Here is my configuration.

Step 1

#dns domain-lookup outside

#DNS server-group DefaultDNS

#name-server 8.8.4.4

Step 2

#object network OBJ-FACEBOOK.COM

#fqdn facebook.com

Step 3

#access-list ACL-inside line 1 extended deny ip any object OBJ-FACEBOOK.COM

#access-list Acl-inside line 1 extended permit ip any any

#access-group ACL-inside in interface Inside

When I do show dns, it does show 

Name: facebook.com
Address: 31.13.65.36 

However when I try to visit any website, it says unable to resolve. Somebody please tell me what is wrong with the configuration.

Thank you for your time.

4 Replies 4

Marvin Rhoads
Hall of Fame
Hall of Fame

You seem to have summarized what you typed. For instance, you would not specify both ACL entries as line 1.

Please share the output of "show run access-list".

Also please run a packet-tracer as follows:

packet-tracer input inside udp <your host address> 1025 8.8.4.4 53

...and share the output.

Thank you Marvin for your response:

Below is the result of the  show run access-list command.

Before

osa-ASA5510fw# show run access-list
access-list Inside_mpc extended permit ip user LOCAL\godey 192.168.0.0 255.255.255.0 any
access-list Outside_access_in extended permit tcp any object WWW-SERVER eq www
access-list traffic_for_ips extended permit ip any any
access-list Outside_mpc extended permit ip any any
access-list global_mpc extended permit ip any any
access-list wccp-servers extended permit ip host 192.168.0.20 any
access-list wccp-traffic extended permit ip 192.168.0.0 255.255.255.0 any
access-list Acl-inside extended permit ip any any
osa-ASA5510fw#


After

access-list Inside_mpc extended permit ip user LOCAL\godey 192.168.0.0 255.255.255.0 any
access-list Outside_access_in extended permit tcp any object WWW-SERVER eq www
access-list traffic_for_ips extended permit ip any any
access-list Outside_mpc extended permit ip any any
access-list global_mpc extended permit ip any any
access-list wccp-servers extended permit ip host 192.168.0.20 any
access-list wccp-traffic extended permit ip 192.168.0.0 255.255.255.0 any
access-list ACL-inside extended deny ip any object OBJ-FACEBOOK.COM
access-list Acl-inside extended permit ip any any
osa-ASA5510fw#

Packet-tracer output:

osa-ASA5510fw(config)# packet-tracer input Inside udp 192.168.0.6 1025 8.8.4.4$

Phase: 1
Type: ROUTE-LOOKUP
Subtype: input
Result: ALLOW
Config:
Additional Information:
in 0.0.0.0 0.0.0.0 Outside

Phase: 2
Type: ACCESS-LIST
Subtype:
Result: DROP
Config:
Implicit Rule
Additional Information:

Result:
input-interface: Inside
input-status: up
input-line-status: up
output-interface: Outside
output-status: up
output-line-status: up
Action: drop
Drop-reason: (acl-drop) Flow is denied by configured rule

You said that "For instance, you would not specify both ACL entries as line 1" I am new to this firewall configuration, could you please tell what should the correct order to write the entries.

Thank you. 

You have two ACLs with similar names:

access-list ACL-inside extended deny ip any object OBJ-FACEBOOK.COM
access-list Acl-inside extended permit ip any any

Notice the first one begins with ACL as three capital letters. I suspect that is the one you have applied with the access-group command. Thus the second entry never catches the remaining traffic and it is all dropped as phase 2 in the packet-tracer output indicates. 

Please confirm with the output of 

show run access-group

If my suspicion is correct then add a second entry as follows:

conf t
access-list ACL-inside extended permit ip any any
end
wr mem

...and then re-run the earlier packet-tracer command. 

Thank you Marvin,

Output for show run access-group

Below:

access-group ACL-inside in interface Inside

osa-ASA5510fw(config)# show run access-li
osa-ASA5510fw(config)# show run access-list
access-list Inside_mpc extended permit ip user LOCAL\godey 192.168.0.0 255.255.255.0 any
access-list Outside_access_in extended permit tcp any object WWW-SERVER eq www
access-list traffic_for_ips extended permit ip any any
access-list Outside_mpc extended permit ip any any
access-list global_mpc extended permit ip any any
access-list wccp-servers extended permit ip host 192.168.0.20 any
access-list wccp-traffic extended permit ip 192.168.0.0 255.255.255.0 any
access-list ACL-inside extended deny ip any object OBJ-FACEBOOK.COM
access-list ACL-inside extended permit ip any any
access-list Acl-inside extended permit ip any any
osa-ASA5510fw(config)#

osa-ASA5510fw(config)# show dns
Name: facebook.com
Address: 31.13.70.36 TTL 00:00:18
Address: 157.240.3.35 TTL 00:04:30

For some reason I must have missed something, right now is not even blocking facebook

Thank you for your time.

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