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ASA 5505 Denying Internal Traffic

I have posted my running config on my asa 5505 as well as error messages about denying traffic. Any help is appreciated.

Error messages:

Deny inbound UDP from 192.168.1.180/53 to FTPserver/63601 due to DNS Response

Deny inbound UDP from 192.168.1.180/389 to FTPserver/1412 on interface inside

Running config:

Result of the command: "sh run"

: Saved
:
ASA Version 7.2(4)
!
hostname ciscoasa
domain-name default.domain.invalid
enable password encrypted
passwd  encrypted
names
name x.x.x.38 OutsideIP
name 192.168.1.154 FTPserver
!
interface Vlan1
 nameif inside
 security-level 100
 ip address 192.168.1.1 255.255.255.0
!
interface Vlan2
 nameif outside
 security-level 0
 ip address OutsideIP 255.255.255.252
!
interface Ethernet0/0
 switchport access vlan 2
!
interface Ethernet0/1
!
interface Ethernet0/2
!
interface Ethernet0/3
!
interface Ethernet0/4
!
interface Ethernet0/5
!
interface Ethernet0/6
!
interface Ethernet0/7
!
ftp mode passive
dns domain-lookup inside
dns server-group DefaultDNS
 domain-name default.domain.invalid
same-security-traffic permit inter-interface
access-list outside_access_in extended permit tcp any 192.168.1.0 255.255.255.0 eq ftp
access-list outside_access_in extended permit tcp any 192.168.1.0 255.255.255.0 eq ftp-data
access-list outside_access_in extended permit tcp any host OutsideIP eq ftp
access-list outside_access_in extended permit tcp any host OutsideIP eq ftp-data
pager lines 24
logging enable
logging asdm informational
mtu inside 1500
mtu outside 1500
icmp unreachable rate-limit 1 burst-size 1
icmp deny any outside
asdm image disk0:/asdm-524.bin
no asdm history enable
arp timeout 14400
global (outside) 1 interface
nat (inside) 1 0.0.0.0 0.0.0.0
static (inside,outside) tcp interface ftp FTPserver ftp netmask 255.255.255.255
static (inside,outside) tcp interface ftp-data FTPserver ftp-data netmask 255.255.255.255
static (outside,inside) tcp FTPserver ftp OutsideIP ftp netmask 255.255.255.255
static (outside,inside) tcp FTPserver ftp-data OutsideIP ftp-data netmask 255.255.255.255
access-group outside_access_in in interface outside
route outside 0.0.0.0 0.0.0.0 x.x.x.37 1
timeout xlate 3:00:00
timeout conn 1:00:00 half-closed 0:10:00 udp 0:02:00 icmp 0:00:02
timeout sunrpc 0:10:00 h323 0:05:00 h225 1:00:00 mgcp 0:05:00 mgcp-pat 0:05:00
timeout sip 0:30:00 sip_media 0:02:00 sip-invite 0:03:00 sip-disconnect 0:02:00
timeout sip-provisional-media 0:02:00 uauth 0:05:00 absolute
http server enable
http 192.168.1.0 255.255.255.0 inside
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
dhcpd address 192.168.1.2-192.168.1.129 inside
!

!
class-map inspection_default
 match default-inspection-traffic
!
!
policy-map type inspect dns preset_dns_map
 parameters
  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 icmp
!
service-policy global_policy global
prompt hostname context
Cryptochecksum:
: end
0
progonosko
Asked:
progonosko
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1 Solution
 
lrmooreCommented:
In both error messages, both the source and the destination are local to the inside interface so the firewall can't do anything with it. You can ignore these error messages.
What does not work?
From the ASA console can you ping your next hop router? If yes, then what are you using for DNS? Internal dns server? You don't have any configured in the dhcpd scope.
0
 
progonoskoAuthor Commented:
The problem is that when the FTPserver tries to browse the network, these messages come up, and that machine is unable to see the internal network. The initial messages that display (as above) are the FTP box trying to get to the internal DNS servers. I should have mentioned that this network has 2 gateways. The FTP is using one and the DNS servers are using the other.
0
 
progonoskoAuthor Commented:
More points. Anyone?
0
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lrmooreCommented:
If both the FTP server and the DNS servers are on the same IP subnet, they should still be able to talk to each other and you can still ignore these error messages.
Add this to the ASA
 sysopt noproxyarp inside

0
 
progonoskoAuthor Commented:
lrmoore,

This seems to be working. Bear with me for a day or so so I can verify that it will work in production and I will give you the points. Thanks for your help. I'll throw in an extra 100 points if  you give me a brief explanation (or a link) as to why it works.
0
 
progonoskoAuthor Commented:
It's still working. As promised - 100 extra points. Thanks, lrmoore.
0
 
progonoskoAuthor Commented:
This completely cleared up the problem. Thanks, lrmoore.
0

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