Need NAT/Reules help with VPN and RPC email access

[oneseven73]

I am unable to get RPC email or client vpn access to an Cisco ASA 5505. I have 3 interfaces, internal, external, and ASDM (managment). No DMZ

Here is the config. Any ideas on what im missing?

: Saved
:
ASA Version 7.2(4)
!
hostname ciscoasa
domain-name default.domain.invalid

names
!
interface Vlan1
nameif ADSM
security-level 100
ip address 192.168.1.1 255.255.255.252
management-only
!
interface Vlan2
no forward interface Vlan1
nameif outside
security-level 0
ip address 19x.xxx.xxx.xxx 255.255.255.248
!
interface Vlan12
nameif inside
security-level 100
ip address 192.168.96.1 255.255.255.0
!
interface Ethernet0/0
switchport access vlan 2
!
interface Ethernet0/1
!
interface Ethernet0/2
switchport access vlan 12
!
interface Ethernet0/3
switchport access vlan 12
!
interface Ethernet0/4
switchport access vlan 12
!
interface Ethernet0/5
switchport access vlan 12
!
interface Ethernet0/6
switchport access vlan 12
!
interface Ethernet0/7
switchport access vlan 12
!
ftp mode passive
clock timezone CST -6
clock summer-time CDT recurring
dns server-group DefaultDNS
domain-name default.domain.invalid
dns server-group ExternalDNS
dns server-group InternalDNS
domain-name xxxxxxxxxxxxxxxx
same-security-traffic permit inter-interface
same-security-traffic permit intra-interface
object-group service DM_INLINE_TCP_1 tcp
port-object eq www
port-object eq https
port-object eq smtp
object-group service DM_INLINE_TCP_2 tcp
port-object eq www
port-object eq https
port-object eq smtp
object-group service DM_INLINE_TCP_3 tcp
port-object eq www
port-object eq https
port-object eq smtp
access-list inbound extended permit tcp any interface outside eq smtp
access-list outside_access_in extended permit tcp any host 19x.xxx.xxx.xxx eq www
access-list outside_access_in extended permit tcp any host 19x.xxx.xxx.xxx eq https
access-list outside_access_in extended permit icmp 192.168.96.0 255.255.255.0 any
access-list outside_access_out extended permit tcp 192.168.96.0 255.255.255.0 any object-group DM_INLINE_TCP_1
access-list inside_access_in extended permit tcp 192.168.96.0 255.255.255.0 any object-group DM_INLINE_TCP_2
access-list inside_access_in extended permit icmp 192.168.96.0 255.255.255.0 any
access-list inside_access_in extended permit udp 192.168.96.0 255.255.255.0 any
access-list inside_access_out extended permit tcp 192.168.96.0 255.255.255.0 any object-group DM_INLINE_TCP_3
pager lines 24
logging enable
logging asdm informational
mtu ADSM 1500
mtu outside 1500
mtu inside 1500
icmp unreachable rate-limit 1 burst-size 1
asdm image disk0:/asdm-524.bin
no asdm history enable
arp timeout 14400
global (outside) 1 interface
nat (ADSM) 1 0.0.0.0 0.0.0.0
nat (inside) 1 0.0.0.0 0.0.0.0
static (inside,outside) tcp interface smtp 19x.xxx.xxx.xxx smtp netmask 255.255.255.255
static (inside,outside) tcp interface

http://www 19x.xxx.xxx.xxx

http://www netmask

255.255.255.255
static (inside,outside) tcp interface https 19x.xxx.xxx.xxx https netmask 255.255.255.255
access-group outside_access_in in interface outside
access-group outside_access_out out interface outside
access-group inside_access_in in interface inside
access-group inside_access_out out interface inside
route outside 0.0.0.0 0.0.0.0 19x.xxx.xxx.1 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 ADSM
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

!
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
!
service-policy global_policy global
prompt hostname context
Cryptochecksum:a9ef2761db884b54abdb7bc8ffb07338
: end
asdm image disk0:/asdm-524.bin
no asdm history enable

 

[rbradely]

you will need a crypto map and isakmp configured and enabled to terminate your vpn connection to the ASA.

on the email:
static (inside,outside) tcp interface https 19x.xxx.xxx.xxx https netmask 255.255.255.255

is 19x.xxx.xxx.xxx the private ip address?
outside_access_in would indicate it is public.

you may want to remove
access-group outside_access_out out interface outside
access-group inside_access_out out interface inside
until you get things working.
You also may want to re-evaluate what these are logically doing.

 

[oneseven73]

Ive removed the access-group outside_access_out and inside_access_out, and the 19x.xxx.xxx.xxx is a public ip. One of the problems i think is the fact that ive got a static route to a router that is blocking external dns access on the internal network. I should only need port 443 for rpc/https correct? I assume i need a route from my any outside to my exchange server over port 443. Thanks for the suggestions.

 

[rbradely]

yes you should only need https for rpc.

the static cmd should read:
static (inside,outside) tcp outside.ip.addr https inside.ip.addr https netmask 255.255.255.255

using 'interface' as the outside address will overload the outside interface. you are also overloading the interface with 'global (outside) 1 interface'. You could use an ACL that didn’t include any ip addresses you plan to use with PAT.

if you have multiple public ip address, and you are not using them all, I would suggest dedicating an unused one for hosting https(back to mail server).

>static route to a router that is blocking external dns access on the internal network
I’m not an email expert but…
You shouldn’t need this to connect to your firewall from the outside. You will need to use your MX record as you server address. Your MX record will be resolvable externally, regardless of internal DNS setups.

 

[oneseven73]

Well, In desperation, I went back to the factory default settings. Problem 1. I cant DNS resolution to work. I have an internal dns at 192.168.69.11, and 2 dns servers outside on the internet at 19x.xxx.xxx.71 and .79 . I can get any address to resolve internally on the 192.168 net, but no addresses outside, like google or yahoo. Do I need a route from my internal dns host to .71 or .79?

If I have 3 static ips (say .201 and .202 and .203), how do I get these to route to my inside network on specific ports, like 443, 25, etc. ? I want to avoid a potential choke point, the interface is on .201 .

Thanks for your help. This is a crazy way to try and learn about the asa.

 

[rbradely]

Problem 1. DNS resolution.

Are these public DNS servers setup as forwarders?

if so the route would be:
route outside 0.0.0.0 0.0.0.0 19x.xxx.xxx.1 1

otherwise were are they located?

do you have nat setup:
access-list inside_local_nat_1 permit ip 192.168.69.0 255.255.255.0 any
nat (inside) 1 access-list inside_local_nat_1
global (outside) 1 interface

can you post your current config?

I have 3 static ips....

static (inside,outside) tcp x.x.x.201 443 192.168.69.101 443 netmask 255.255.255.255
static (inside,outside) tcp x.x.x.202 80 192.168.69.102 80 netmask 255.255.255.255
static (inside,outside) tcp x.x.x.203 25 192.168.69.103 25 netmask 255.255.255.255

access-list outside_access_in permit tcp any host x.x.x.201 eq 443
access-list outside_access_in permit tcp any host x.x.x.202 eq 80
access-list outside_access_in permit tcp any host x.x.x.203 eq 25

access-group outside_access_in in interface outside

All can be directed to the same server on a different port or three different servers.

 

[oneseven73]

I had the dns issue fixed, now its broken again. I have added these rules:

static (inside,outside) tcp [internal dns] 53 [external dns supplied by isp] 53
static (inside,outside) udp [internal dns] 53 [external dns supplied by isp] 53

I am guessing this should route external name resolution requests to the external DNS. Inside network server name resolution works fine. All outside dns requests time out.

I actually had it working, but zapped my config again since an ACL was halting 80 and 443 requests to an inside host. I was pounding my head as i had an aCL that said "anything coming from any address outside the outside interface permitted to access (host ip) on inside interface using ports 80 or 443." Dont know why this was being overlooked by the 5505.

Anyone know what else could be blocking the outside DNS access causing the request timeout, or have a solution?

Thanks.

 

[rbradely]

no it will not route external name resolution requests to the external DNS.

The forwarders configured on your DNS server is how external resolution will take place.

What ACLs are configured?

>I actually had it working, but zapped my config again since an ACL was halting 80 and 443 requests to an inside host.

Internal connection going outbound will be allowed back into the network if they are part of the initial packet stream.

this could be an issue:
access-group inside_access_in in interface inside