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thombie

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Internet failover on Cisco 3900

I  Have an Internet router with 2 Interconnection from the same supplier.  ( not ideal I know)

what the best way to set auto failover.
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Predrag Jovic
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Generally, you would use tracking object (IP SLA) to track if some remote destination is available. If tracking object is equal FALSE (object not reachable through preferred WAN interface) then other WAN interface should be used for traffic forwarding. So, two static routes with tracking object should be created. When primary default route is not able to forward traffic to destination secondary default route should be placed in routing table instead of primary default route.

Do you have separate IP address range that is used for natting, other than IP address ranges that are present on your WAN interfaces?
The reason for asking than question is - if you are natting traffic with IP address range that is present on each WAN interface than all TCP sessions will be broken during failover.
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Jordan Taylor
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ask youre provider to do dynamic routing with BGP on the 2 uplinks.
this will make it much more stabele. and fail over is full automated.

to have full redundancy you have to buy a second router. and do vrrp on the local side
and ibp to redir the routes and ebgp to youre provider. then youre setup is perfect
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thombie

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Thanks for the advice