Although this not a feature that is supported natively on the ProxySG, it is possible to apply web filtering category based routing to the policy.
For this example, we have a proxy installed (inline or explicit) that is connected to a routing device that has access to both ISPs. ISP-A is a high speed connection dedicated to mission critical traffic, and ISP-B is a slower connection that we want to use for recreational traffic.
The proxy's main IP address is 10.1.1.10, and the default gateway is the router at 10.1.1.1
(LAN) -> (Proxy) -> Router capable of doing source-based routing -> ISP A and B
The way we can do this is by using the "reflect client IP" feature for some of the connections, and then let the router decide which ISP to use based on source IP.
Your router will now see traffic coming from 2 different IP addressed, 10.1.1.10 (for connections that didn't match our rule, so mission critical traffic), and 10.1.1.11 (for traffic that matched our recreational web filtering categories)
What you need to configure now, and this will vary depending in the router you use, is a source IP based route that should be something like this :
This is not a "cookie cutter" solution, you might need to make a few chances to it depending on your environment. Since category based routing is not a ProxySG feature yet, this is the only way to route traffic depending on category.
Contribution from nolan.rumble from forums.bluecoat.com