Sam Ruby: Port Forwarding

Problem: I’m not always at the machine that is VPN’ed into work.

Solution: place the following into /etc/network/if-up.d/sametime-forwarder:

#!/bin/sh
#
# redirect Sametime's port 1533 to messaging.ibm.com
#
echo 1 > /proc/sys/net/ipv4/ip_forward # turns on forwarding
iptables -F -t nat # Flush existing translation tables
iptables -t nat -A PREROUTING -p tcp --dport 1533 -j DNAT --to 9.17.136.77:1533
iptables -t nat -A POSTROUTING -j MASQUERADE