The TMG firewall includes a new feature called ISP failover. This feature enables the TMG firewall to use multiple ISPs, either for load balancing, so that both ISPs are used at the same time, or for failover and failback – where one ISP is used until it goes down, and then the other ISP is used.

This feature works pretty good and is relatively easy to configure. Some of the documentation is dicey, so you’re likely going to do a bit of trial and error before you get it working right. But once you do, you’ll be happy with the results.

But what about the lowly, sad, pathetic and discredited “hork mode”?

You know – Hork Mode! If you’ve been following this space for a while, hork mode is the name for a caponized ISA or TMG firewall – caponized because it only has a single NIC. Hork mode is reviled in the the ISAserver.org community and the best way to ruin any ISA or TMG firewall Pro’s day is to start it with a question about hork mode.

OK, sure, whatever.

But what about ISP failover and hork mode? For those of you who are forced by political or other evil forces to run your TMG firewall in hork mode, the good news is that ISP failover will work with it! Consider it a piece of meat thrown into the dark dungeon of the life of a hork mode TMG firewall

For some more information about ISP failover, check out:

https://blogs.technet.com/isablog/archive/2009/10/...e.aspx

HTH,

Tom

Thomas W Shinder, M.D., MCSE
Sr. Consultant / Technical Writer

Prowess Consulting www.prowessconsulting.com
PROWESS CONSULTING | Microsoft Forefront Security Specialist
Email: tshinder@isaserver.org
MVP — Forefront Edge Security (ISA/TMG/IAG)