outside host blocked
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11-08-2012 03:46 AM - edited 03-11-2019 05:20 PM
I have a host on the outside i want to access
the problem is ASA 5505 has somehow blocked traffic to this host
i can find nothing in the shun list and there is no ACL rule stating that this specific host is blocked.
Where else can i check to see if it's blacklisted.
My home computer that is not behind any firewall easily access this host.
The host is also blocked from accessing the webpage behind my ASA
Also this website my home computer can access without any problems.
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NGFW Firewalls
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11-08-2012 07:35 AM
Hi,
If you generate the traffic from inside to outside, you dont need ACL, and the ASA will know the returne traffic and allow that.
So you have something else that block it, can you ping that host from the firewall itself?
can you give more info about the network so we can help you?
Regards,
MKD
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11-08-2012 10:39 PM
i have 1 webserver behind the ASA and alot of client computers.
i have 2 ubuntu computers outside directly to the internet they both run ftp servers.
I have my home computer that is not behind ASA
The clients on the inside wants to access both ubuntu ftp servers
Ubuntu 1 works great no problems whatsoever traceroute,ping,ftp,http.
Ubuntu 2 gets timeout on ftp client and no response to ping, traceroute, http.
On my home computer i can access both ubuntu servers perfectly fine.
When i logon to the ubuntu computers and start firefox to try and access the webserver behind the ASA
Ubuntu 1 works fine and no problems at all.
Ubuntu 2 gets server not responding.
here is my show access-list
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11-11-2012 10:44 PM
Really no one who has any ideas on what it could be?
i've tried disabling basic threat detection but i see no difference.

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11-12-2012 05:55 PM
Pls kindly share the ASA configuration, as well as the IP Address of client on the inside that you are trying to access those 2 Ubuntu server, and also the IP Address of both servers.
Are you trying to access the server by IP Address or by FQDN?
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11-12-2012 10:33 PM
running configuration at
http://dev.inetpro.org/pastebin/1647
trying to access server by ip and dns name
inside client ip is 192.168.1.34
banned host has 87.253.75.44
the ASA outside ip is 87.253.75.42
non blocked host has ip 87.253.75.43
Also tried accessing the http that is behind the ASA and that only works from 87.253.75.43 and the 87.253.75.44 gets ACL denied
3 | Nov 12 2012 | 16:14:46 | 710003 | 87.253.75.44 | 35168 | 87.253.75.42 | 80 | TCP access denied by ACL from 87.253.75.44/35168 to inside:87.253.75.42/80 |

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11-13-2012 01:15 AM
Your class map has been incorrectly configured.
You are matching any traffic and inspect it against PPTP and FTP which is incorrect.
You should only match it against the default protocol and ports.
To make it easy, just use the default inspection policy as follows:
class-map inspection_default
match default-inspection-traffic
policy-map global_policy
class inspection_default
inspect ftp
inspect pptp
inspect icmp
no service-policy global-policy-vpn global
service-policy global_policy global
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11-13-2012 01:22 AM
Ok did what you suggested but i still have the same problem
new running config

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11-13-2012 03:42 AM
Did you "clear xlate" after making the changes and try again?
Also, if you run packet tracer, where is it failing?
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11-13-2012 03:56 AM
cleared xlate
Bsldurssonfw# clear xlate
INFO: 528 xlates deleted
Still no go
Packet tracer is sucessful
But still cannot access the host in question.
did a packet trace from inside 192.168.1.34 TCP 80
to 87.253.75.44 TCP 80
and it was "allowed"

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11-13-2012 04:36 AM
If packet tracer is successful, then it is not issue on the ASA.
I would check the host itself.
Does it have dual NIC, or just the one NIC? is packet actually getting to it? and is it replying?
Are you able to ping the host from the ASA itself? Does the ASA have the correct ARP for that host?
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11-13-2012 04:40 AM
the ASA is blocking it somehow.
i have remote control over the blocked host and if i open up a browser on it and surf to the ASA ip and i'm logging the connect attempt ASA logging is giving me this
3 | Nov 13 2012 | 13:32:01 | 710003 | 87.253.75.44 | 35293 | 87.253.75.42 | 80 | TCP access denied by ACL from 87.253.75.44/35293 to inside:87.253.75.42/80 |
on a computer not behind the ASA there is no problems getting to 87.253.75.44
but no clients behind the ASA can access it.
not sure what you mean by correct ARP host.

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11-13-2012 04:44 AM
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11-13-2012 04:51 AM
Done this also and no go.
it is only this ip 87.253.75.44 that is blocked in the ASA
another host 87.253.75.43 can access the www page behind the ASA without any problems.

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11-13-2012 04:57 AM
If packet tracer is successful from and to 87.253.75.44, then it is unlikely it is an issue with the ASA.
If you change the ip address of the host to a different address, does it work? what is the default gateway of that host?
