We have a MPLS network between to datacenter locations. Between the core nodes we have 1 Gbps Ethernet links transported via a DWDM network.
We are now in the process of upgrading the capacity between the datacenters.
The final solution is to implement 10 Gbps, but as a fast solution to have more capacity we are planning to install 1 more GigE link between to of the core nodes. This is a temporary solution to quickly implement more bandwidth.
See attached simplified network drawing.
We are planning to use OSPF ECMP on the links between core1 and core3. All nodes are 6500 with 67xx interfaces. The two links between core1 and core3 have different paths in the DWDM transport network, which will give a slight difference in latency.
My questions are:
1. Is this a safe configuration?
2. Is "per-destination load-sharing" default behavior on IOS based 6500 (12.33.SXI1)
3. Are there any issues we have to take into consideration before implementing?