Here's the edited config. Basically the Exchange server has a NAT rule to allow http/https/smtp, which is how the ARP issue arose. Would the ARPRetryCount command be any use, if I enable proxyarp again?
: Written by enable_15 at 11:01:37.416 UTC Tue Apr 3 2012
!
ASA Version 8.2(5)
!
hostname
enable password xxxxxxxxxxxxxxxx encrypted
passwd xxxxxxxxxxxxxxxx encrypted
names
name 10.48.254.0 vpnclients-network
name srvex01-external
name 10.48.1.3 srvex01-internal
name scotty-external
!
interface Ethernet0/0
nameif outside
security-level 0
ip address 255.255.255.248
!
interface Ethernet0/1
nameif inside
security-level 100
ip address 10.48.1.254 255.255.0.0
!
interface Ethernet0/2
shutdown
no nameif
no security-level
no ip address
!
interface Ethernet0/3
shutdown
no nameif
no security-level
no ip address
!
interface Management0/0
shutdown
nameif management
security-level 0
no ip address
management-only
!
ftp mode passive
object-group service DM_INLINE_TCP_1 tcp
port-object eq www
port-object eq https
port-object eq smtp
access-list inside_nat0_outbound extended permit ip any vpnclients-network 255.255.255.192
access-list outside_access_in extended permit tcp any host srvex01-external object-group DM_INLINE_TCP_1
pager lines 24
logging enable
logging asdm informational
mtu outside 1500
mtu inside 1500
mtu management 1500
ip local pool vpnclients 10.48.254.1-10.48.254.32 mask 255.255.0.0
icmp unreachable rate-limit 1 burst-size 1
icmp deny any outside
no asdm history enable
arp timeout 14400
global (outside) 101 interface
nat (inside) 0 access-list inside_nat0_outbound
nat (inside) 101 0.0.0.0 0.0.0.0
static (inside,outside) srvex01-external srvex01-internal netmask 255.255.255.255
static (outside,inside) srvex01-internal srvex01-external netmask 255.255.255.255
access-group outside_access_in in interface outside
route outside 0.0.0.0 0.0.0.0 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
timeout floating-conn 0:00:00
dynamic-access-policy-record DfltAccessPolicy
http server enable
http 10.48.0.0 255.255.0.0 inside
no snmp-server location
no snmp-server contact
snmp-server enable traps snmp authentication linkup linkdown coldstart
sysopt noproxyarp inside
crypto ipsec transform-set ESP-3DES-SHA esp-3des esp-sha-hmac
crypto ipsec transform-set ESP-AES-256-MD5 esp-aes-256 esp-md5-hmac
crypto ipsec transform-set ESP-DES-SHA esp-des esp-sha-hmac
crypto ipsec transform-set ESP-DES-MD5 esp-des esp-md5-hmac
crypto ipsec transform-set ESP-AES-192-MD5 esp-aes-192 esp-md5-hmac
crypto ipsec transform-set ESP-3DES-MD5 esp-3des esp-md5-hmac
crypto ipsec transform-set ESP-AES-256-SHA esp-aes-256 esp-sha-hmac
crypto ipsec transform-set ESP-AES-128-SHA esp-aes esp-sha-hmac
crypto ipsec transform-set ESP-AES-192-SHA esp-aes-192 esp-sha-hmac
crypto ipsec transform-set ESP-AES-128-MD5 esp-aes esp-md5-hmac
crypto ipsec security-association lifetime seconds 28800
crypto ipsec security-association lifetime kilobytes 4608000
crypto dynamic-map SYSTEM_DEFAULT_CRYPTO_MAP 65535 set pfs group1
crypto dynamic-map SYSTEM_DEFAULT_CRYPTO_MAP 65535 set transform-set ESP-AES-128-SHA ESP-AES-128-MD5 ESP-AES-192-SHA ESP-AES-192-MD5 ESP-AES-256-SHA ESP-AES-256-MD5 ESP-3DES-SHA ESP-3DES-MD5 ESP-DES-SHA ESP-DES-MD5
crypto map outside_map 65535 ipsec-isakmp dynamic SYSTEM_DEFAULT_CRYPTO_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
telnet timeout 5
ssh timeout 5
console timeout 0
threat-detection basic-threat
threat-detection statistics access-list
threat-detection statistics tcp-intercept rate-interval 30 burst-rate 400 average-rate 200
ntp server 10.48.1.2 source inside
webvpn
group-policy DfltGrpPolicy attributes
banner value ** Warning: you are connecting to the network. **
banner value
banner value This connection is for authorised users only. If you are not authorised to use this connection you should disconnect immediately. For acceptable use guidelines please refer to the Company IT Policy (HR 062).
group-policy clientvpn internal
group-policy clientvpn attributes
dns-server value 10.48.1.2
vpn-tunnel-protocol IPSec
default-domain value .local
username password oMmrrMbNRhqeKCzM encrypted privilege 0
username attributes
vpn-group-policy clientvpn
username password CPuKILOZBCZIv1IN encrypted privilege 0
username attributes
vpn-group-policy clientvpn
tunnel-group clientvpn type remote-access
tunnel-group clientvpn general-attributes
address-pool vpnclients
default-group-policy clientvpn
tunnel-group clientvpn ipsec-attributes
pre-shared-key *
!
class-map inspection_default
match default-inspection-traffic
!
!
policy-map type inspect dns preset_dns_map
parameters
message-length maximum client auto
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 sqlnet
inspect skinny
inspect sunrpc
inspect xdmcp
inspect sip
inspect netbios
inspect tftp
inspect ip-options
!
service-policy global_policy global
prompt hostname context
no call-home reporting anonymous
Cryptochecksum:fc67b04ada9eb738b4a9f63b93cb1400
