[c-nsp] Is this possible with OSPF?

[Garry]

Hi,

I have a remote site connected via two links at separate places in our
network. One link (stm1) is the primary route, the second (50M) is
mostly backup link. So far it's rather easy, using OSPF cost entries in
the interfaces will take care of that. Anyway, the backup link also has
a couple of other sites connected in a /27 broadcast net (via a virtual
switch in the WAN). Those sites (which only have that one uplink)
announce local addresses (e.g. loopback interfaces) that are used for
VPN tunnels. Those IPs should be routed via this vswitch link instead of
the primary link. Which of course means that by setting the OSPF cost on
the interface, the priority would be lowered, and the routing via the
regular link would be used ...
Is there any way (route maps?) to alter the OSPF cost just for certain
prefixes? I could probably use some tracking and stuff to use static
routes with lower admin cost to get similar results, but that would
lower convergence times in case of link failures (I'm using 3 hellos per
second for quick failover of the links)

Tnx, Garry