[c-nsp] BGP questions

[Sargon]

I have three peering sessions. One is a 100Mbps Internet2 connection 
(call this I2). The second is a 60Mbps rate-limited to 20 Mbps (call 
this one ISP-I). These are in a 7513. The third is on a different 
router, and is a 100Mbps connection (call this one ISP-R). It is in a 
7206VXR.

I have local prefs and route maps in place to force all I2 traffic 
through the I2 link. A route map and local prefs force all non-I2 
traffic destined for ASs within ISP-I's network through that link. 
All other traffic then crosses the GE link between the two routers 
and passes through ISP-R's link.

I also have two 6509s. 6509-A has an iBGP peer with the 7513 and the 
7206. 6509-B has an iBGP peer with the 7206 and the 7513. Thre is no 
iBGP session between the 6509s.

The 7513 sends a default route and a distribute list (permit 0.0.0.0) 
to 6509-A, but no the the second 6509. The 7206 sends a default route 
and a distribute list (permit 0.0.0.0) to 6509-B, but not the first 
6509.

If the GE link between the routers dies, hosts which are connected to 
6509-A have problems with non-I2 traffic. Traffic (obviously) exits 
the ISP-I link, but then tries to come back via ISP-R, and there is 
no way for that traffic (currently) to exit 6509-B to get back to 
them.

What is the recommended way to deal with this? My redundant fiber 
going to the second 6509 will not be in place for a few more months, 
and I have been ordered to fix the asymmetric routing.

All suggestions will be greatly appreciated.