Using User Defined Routing to control what is sent over ExpressRoute tunnel

Sign in to queue

The Discussion

  • User profile image

    Good detailed pace, but I would add two things:
    1. A demo of the actual settings in the ARM console would be good.
    2. There's a use-case that you didn't mention which I have come across: the fact that if BGP doesn't advertise a route to the vnet, you can't override it (or more accurately add to it) with a UDR. So, BGP may say "I know anout and" for example. What you can't then do is throw 0/0 at ExpressRoute with a simple UDR. (Hint: it might be good to allow this as, with your major PaaS competitor, this is possible.) So, what you might do is call the WAN provider and ask them to advertise 0/0 down the ER pipe. But now it grabs all the data. What you can do is then create a UDR to effectively "override" the BGP route. IOW, get the WAN provider to advertise everything including the kitchen sink, and then effectively cancel out the routes you don't want. (With your major PaaS competitor, this isn't necessary as you can "push" routes down their equivalent of ER with cloud-based routes even if the routes arrive via BGP.)

Add Your 2 Cents