Hi,
Could this idea work ??
In the attached diagram 2 x 4Mbit internet pipes have been obtained from 1 ISP. Both in active / active mode.
Outgoing Traffic:
The 2 CE routers at the customer site both have full BGP IP tables for the internet. They pass a default route to the ASA's (or the ASA's simply point a default route to the directly connected CE Router). The 2 CE routers both provide the same customer address space and connect to the ASA's on the same subnet / Vlan.
The ASA's connect to our core routers over Dot1q trunks and perform NAT for our internal 172.16.0.0 address range into the IS provided customer address space for the Internet.
The ASA's participate in OSPF routing with the MA core routers and carry out a default information originate, or the Core routers simply use a default route pointing to the ASA's over each Dot1q trunk.
Each core router then has an equal cost path through each CE router to get out onto the internet.
Incoming Traffic:
Because BGP cannot load balance in the ISP cloud, incoming traffic will only ever take one path back to the customer site (which ever BGP metric is used - weight, pref, MED etc).
Therefore, configure static routes within the ISP cloud on the aggregate router for the 2 ISP CE Routers.
2 Static routes are configured pointing to the customer internal network via each CE router.
This should then load balance incoming traffic over each CE router.
Thanks in advance.
