I have a Microsoft ISA Server located behind a Cisco 800 router. The router has a public IP address and the ISA
Server has a private address. I am unable to reach my ISA Server from outside the router because the router is blocking my connections. What do I need to do to reach the ISA Server? Because your router's external interface has a public IP address and its internal interface has a private IP address, the problem you are experiencing is probably caused by Network Address Translation (NAT) on the router. Incoming connections from the Internet to your ISA server cannot reach your ISA server unless a static NAT mapping makes the ISA server reachable through the router's public IP address.
You did not say which Cisco 800 model you are using, but there's a good NAT configuration tip for reaching internal Web servers through Cisco 827 routers posted on Cisco's website. This tip describes configuration port 80 configuration for a web server, but a similar configuration can be used to forward traffic to other internal servers using other ports. More information on configuring NAT on Cisco 800 series routers in general can be found here.
Dig deeper on Working With Servers and Desktops
Related Q&A from Lisa Phifer, Wireless Networking Expert
Wireless expert Lisa A. Phifer explains to what extent WEP cracking remains a worrisome issue. It all depends on your company's WLAN security policy.continue reading
Wireless expert, Lisa Phifer explains that it may not be worth enhancing Wi-Fi ad hoc mode since Wi-Fi Direct is a better alternative for enabling ...continue reading
Wireless expert Lisa Phifer responds to a question regarding a Mi-Fi and Android smartphone mobile hotspot comparison. She provides an in depth ...continue reading
Have a question for an expert?
Please add a title for your question
Get answers from a TechTarget expert on whatever's puzzling you.