I have a server with 2 NIC's. Default route is added to primary NIC only, as usual. Persistent route added to route table to force traffic to a certain destination subnet out the second NIC. It appears that when the gateway of the second nic is down, or even set to wrong ip address, and traffic needs to use this route to reach the listed destination, after a time it will time out and use the default gateway.
Can you confirm this behavior?