Load Balance with bandwidth limit

[jparsons]

I have a requirement I’m finding hard to come up with a solution.

I have 2 physical separate DCs with a 100G cross connection between them spanning L2 traffic’s and I have a remote site connected via satellite connection.

The remote site has two PE routers located there each connecting back to DC1 and DC2 for redundancy. However given satellite is very expensive we only have a limit of 40mb (total at one time)

Both satellite links are allowed to pass 40mb but for example we would only be allowed 20mb on one and 20Mb on the other. Even though we could route 40mb on one and 40mb on another we are not allowed due to the “agreement” of 40mb at any given time.

How could I use both links to traverse traffic but not go above 40mb total but in the event of link failure all 40mb would flow through the surviving link?

[Joseph W. Doherty]

So you're not allowed to use 40 Mbps on one link while using zero on the other, correct?  If not correct, provide one path a better routing metric so that all your traffic uses it, but if it fails, then all the traffic would shift to your second path (and back if failed path is restored).

If correct, i.e. you really want to use both paths at 20 Mbps each, assuming both are "up", for that, what might be done (much more complicated) is shape each path for 20 Mbps, and monitor links with EEM.  If one path fails, have EEM script increase shaping limit, to 40 Mbps, on remaining path.  If failed path returns, have EEM script reset shaper to 20 Mbps.