Regarding OSPF cost

I am having an MPLS router with its both interfaces connected to core and back up core switches, how can we set the priority so that my primary routing is over core and in case of any failure in core the secondary is through backup core.

I guess i need some geeks here to confirm what i think.

Use HSRP protocol in both core and back up switches and create one virtual ip.

Use this virtual ip as default route in your router's config, so what all data the router receives it sends to this default route(on virtual ip).

I think this should help.

Regards,
Apurva Modh.
CCNP.

As the subject of your post is "OSPF cost" I guess your two links towards core and backup-core are in Layer 3 and you're running OSPF on those links.

You should then simply increase the OSPF cost to a very high value (i.e. higher than the route with the highest cost) on the link towards the backup-core on both side of the link to guarantee symmetric routing.

Hope this help.

Christophe