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New Member

failover default routes

ok, dumb question, but...what determines when a router will reroute packets to an alternate default route that has a higher cost?

ie:

ip route 0.0.0.0 0.0.0.0 1.1.1.1

ip route 0.0.0.0 0.0.0.0 2.2.2.2 150

When will this router determine that it needs to send packets thru the higher cost route?

2 REPLIES
New Member

Re: failover default routes

If 1.1.1.1 ever goes down, it will use 2.2.2.2 to get out. As long as the lower cost route is up, that will be the one it uses.

New Member

Re: failover default routes

Actually it is not a dumb question and I see this mistake very often.

The challenge is, it depends on the situation. It will only failover if the physical interface senses the path to 1.1.1.1 go down. If the other end of the circuit (I'm assuming WAN) has an external CSU (depending on the CSU) and the router gets hosed the line will stay up and traffic will still be forwarded to a non-existing device. Or in a LAN 1.1.1.1 could go down and the router with the default route will never know because the inteface will still have carrier sense and remain up.

What is the situation that you are using the failover in?

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