Route Manipulation

Cory Roulette · ‎08-06-2015

Currently I have 2 Datacenters in my enviroment one is the main DC and the other is the secondary DC. Currently we have 12 branch offices and those branch office all get funneled out to the internet through our main DC. Now we have a requirement to funnel half the sites out the main DC and the other 6 sites out the secondary DC. The main DC is handling the advertisement of the default route I am unsure on how to split the advertisement to force half the sites out secondary DC and half out Primary DC. Not sure where to start short of opening a support ticket or reach out to a 3rd party vendor for help.

Markus Benz · ‎08-08-2015

Hi Cory,

how are you doing the routing today?

You could solve it like this:
Each Branch hast two tunnels, one to each DC. You run OSPF as a routing protocol over the tunnels. And you use a different metric on the two tunnel interfaces, so that one is preferred over the other one.

Regards,
Markus

Cory Roulette · ‎08-10-2015

We are running EIGRP at all sites. When you mention tunnels are you talking about creating GRE tunnels from the 6 sites that need to use the secondary DC for internet access? Then setting the metric on those sites to use the tunnels to get to the internet?

Markus Benz · ‎08-10-2015

You where talking about tunnels in your initial description. So I was assuming you're using some sort of crypto tunnels or GRE.

With EIGRP it is about the same. Just put a delay to one of the interfaces, so EIGRP will prefer the other one:

Router(config)# interface ethernet0/1

Rrouter(config-if)# delay 100

Let me know if that works for you. If not please let me know what your exact setup is.

Regards,
Markus