Configure the outlook client to use RPC over HTTP. Of course, then just forward port 80 inbound to the exchange server.
http://office.microsoft.com/en-us/as...402731033.aspx
The IPTABLES script was created using the "Iptables Script Generator" found at
http://iptables-script.dk/. You will of course have to edit it to reflect your IP addresses etc.. This script assumes that eth0 is your external interface, and eth1 is your internal interface.
#!/bin/sh
# iptables script generator: V0.1-2002
# Comes with no warranty!
# e-mail:
michael@1go.dk
# Disable forwarding
echo 0 > /proc/sys/net/ipv4/ip_forward
LAN_IP_NET='192.168.0.1/24'
LAN_NIC='eth1'
OWA_SERVER='192.168.0.10'
# load some modules (if needed)
# Flush
iptables -t nat -F POSTROUTING
iptables -t nat -F PREROUTING
iptables -t nat -F OUTPUT
iptables -F
iptables -P INPUT DROP
iptables -P FORWARD DROP
iptables -P OUTPUT ACCEPT
# enable Masquerade and forwarding
iptables -t nat -A POSTROUTING -s $LAN_IP_NET -j MASQUERADE
iptables -A FORWARD -j ACCEPT -i $LAN_NIC -s $LAN_IP_NET
iptables -A FORWARD -m state --state ESTABLISHED,RELATED -j ACCEPT
# STATE RELATED for router
iptables -A INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT
# Open ports to server on LAN
iptables -A FORWARD -j ACCEPT -p tcp --dport 80
iptables -t nat -A PREROUTING -i eth0 -p tcp --dport 80 -j DNAT --to $OWA_SERVER:80
# Enable forwarding
echo 1 > /proc/sys/net/ipv4/ip_forward
