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Unable to resolve DNS behind Cisco ASA 5505

Oeyhope asked
Hello all

I am unable to resolve DNS behind my Cisco ASA 5505. Windows server 2008 r2 is setup as the dhcp server and external dns server is configured as forwarders. Here are my asa config. Anyone know where the problem could be?

Result of the command: "sh conf"

: Saved
: Written by enable_15 at 21:39:48.557 UTC Sun Aug 12 2012
ASA Version 8.3(2) 
hostname XXXFW
domain-name xxxxxx.local
enable password yNew3bgX2gTfsqf/h2uCL encrypted
passwd 2KqQnbfwNI.2KYOU encrypted
name proxy
interface Vlan1
 nameif inside
 security-level 100
 ip address 
interface Vlan2
 nameif outside
 security-level 0
 ip address 81.XXX.XXXX.XXX 
interface Vlan3
 nameif dmz
 security-level 50
 ip address dhcp 
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
boot system disk0:/asa832-k8.bin
ftp mode passive
dns server-group DefaultDNS
 domain-name xxxxxx.local
object network obj- 
object network obj- 
object network obj- 
object network obj- 
object network obj- 
object network obj_any 
object network PPTP-server 
object-group protocol TCPUDP
 protocol-object udp
 protocol-object tcp
access-list xxxxvpn_splitTunnelAcl standard permit 
access-list inside_nat0_outbound extended permit ip 
access-list inside_nat0_outbound extended permit ip 
access-list outside_1_cryptomap extended permit ip 
access-list outside_access_in extended permit tcp any host eq 3389 
pager lines 24
logging enable
logging asdm informational
mtu inside 1500
mtu outside 1500
mtu dmz 1500
ip local pool xxxxpool mask
ip local pool xxxx10.26.0.150- mask
no failover
icmp unreachable rate-limit 1 burst-size 1
asdm image disk0:/asdm-634.bin
no asdm history enable
arp timeout 14400
nat (inside,any) source static obj- obj- destination static obj- obj- unidirectional
nat (inside,any) source static obj- obj- destination static obj- obj- unidirectional
object network obj-
 nat (inside,outside) static interface service tcp 3389 3389 
access-group outside_access_in in interface outside
route outside 81.XXX.XXX.XXX 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
timeout tcp-proxy-reassembly 0:01:00
dynamic-access-policy-record DfltAccessPolicy
http server enable
http inside
no snmp-server location
no snmp-server contact
snmp-server enable traps snmp authentication linkup linkdown coldstart
crypto ipsec transform-set ESP-3DES-SHA esp-3des esp-sha-hmac 
crypto ipsec transform-set ESP-DES-MD5 esp-des esp-md5-hmac 
crypto ipsec security-association lifetime seconds 28800
crypto ipsec security-association lifetime kilobytes 4608000
crypto ipsec df-bit clear-df outside
crypto dynamic-map outside_dyn_map 20 set pfs group1
crypto dynamic-map outside_dyn_map 20 set transform-set ESP-3DES-SHA
crypto map outside_map 1 match address outside_1_cryptomap
crypto map outside_map 1 set pfs 
crypto map outside_map 1 set peer xx.XXX.XXX.XXX 
crypto map outside_map 1 set transform-set ESP-3DES-SHA
crypto map outside_map 65535 ipsec-isakmp dynamic outside_dyn_map
crypto map outside_map interface outside
crypto isakmp enable outside
crypto isakmp policy 10
 authentication pre-share
 encryption 3des
 hash sha
 group 2
 lifetime 86400
no crypto isakmp nat-traversal
telnet timeout 5
ssh timeout 5
console timeout 0
dhcpd auto_config outside
dhcpd address inside

threat-detection basic-threat
threat-detection statistics access-list
no threat-detection statistics tcp-intercept
group-policy xxxxxinternal
group-policy xxxxxxxattributes
 wins-server value
 dns-server value
 vpn-tunnel-protocol IPSec 
 split-tunnel-policy tunnelspecified
 split-tunnel-network-list value xxxxx_splitTunnelAcl
 default-domain value xxxxx.local
username attila password Nc7VToimLfa3Cxth encrypted privilege 0
username attila attributes
 vpn-group-policy xxxxx
username knkl password Hb.4ZNcTg6Ketq/w encrypted privilege 0
username knkl attributes
 vpn-group-policy xxxxx
username dach password xSyTYr0x4VCsHEv0 encrypted privilege 0
username dach attributes
 vpn-group-policy xxxxx
username oyvind password oRUppDFe.1zqh7KY encrypted privilege 0
username oyvind attributes
 vpn-group-policy xxxxx
username hagj password rbDKy3hAw01uJJjr encrypted
username hagj attributes
 vpn-group-policy xxxxxx
username kare password wOWJstV5SXfLCARX encrypted privilege 0
username kare attributes
 vpn-group-policy xxxxxx
username xxxxxpassword SQumpZUsgPFi91GI encrypted privilege 0
username xxxxxattributes
 vpn-group-policy xxxxxx
tunnel-group xxxxxtype remote-access
tunnel-group xxxxxxgeneral-attributes
 address-pool xxxxx
 default-group-policy xxxxxx
tunnel-group xxxxxxipsec-attributes
 pre-shared-key *****
tunnel-group 82.xxx.xxx.xxx type ipsec-l2l
tunnel-group 82.xxx.xxx.xxx ipsec-attributes
 pre-shared-key *****
policy-map type inspect dns preset_dns_map
  message-length maximum 512
prompt hostname context 
 profile CiscoTAC-1
  no active
  destination address http https://tools.cisco.com/its/service/oddce/services/DDCEService
  destination address email callhome@cisco.com
  destination transport-method http
  subscribe-to-alert-group diagnostic
  subscribe-to-alert-group environment
  subscribe-to-alert-group inventory periodic monthly
  subscribe-to-alert-group configuration periodic monthly
  subscribe-to-alert-group telemetry periodic daily

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Watch Question

try to add a service policy in ASDM for all the traffic and make sure you are inspecting DNS ,
dns packet should come from your inside interface and go outside and be statefully inpect to permit the dns answer back without the need of an access-list in the outside interface.

use the monitoring tab and see the real time log , filter by the ip address or the dns protocol , and try to see if the packet is going through your asa to the internet .
Pete LongTechnical Consultant
Distinguished Expert 2019

Yeah you have a DNS policy map but you have not got it applied?

issue the following commands

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 sqlnet
  inspect skinny  
  inspect sunrpc
  inspect xdmcp
  inspect sip  
  inspect netbios
  inspect tftp
  inspect icmp
  inspect ipsec-pass-thru
  inspect ip-options
service-policy global_policy global


Thank you for trying to help. unfortunately the commands did not fix the issue :(

Do you have any other tips?
Adding the following command fixed the issue:

object network obj_any
subnet  --> You can replace 0/0 with your internal subnet.
nat (inside,outside) dynamic interface


the command fixed the issue.