I'm currently setting up a multihomed configuration for my organization. Our infrastructure is currently addressed out of our current ISP's /24. We also have direct assignment space which we plan to start addressing out of in the coming months.
My question is this: Can I just advertise the ISP's /24 out their connection, and the direct assignment /24 out the other router, or do I need to advertise both from both routers?
We will load share our connections over both 100mb circuits.
Thanks in advance for any help offered.
Yes you would need to advertise the prefix via both the routers and readdress the existing ISP owned address to the one owned by you
By default, the incoming traffic would choose the link based on AS-path seen from the destination. You could use as-path prepend to make one of the connections less preferable though.
Have a look at this link