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How to load balance and provide failover for two Internet circuits from same ISP 1

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hinesjrh

MIS
Jan 4, 2005
260
US
I have a single Cisco 3845 as my Internet router. Currently I have two 100 Mbps Ethernet circuits from the same ISP, and both of those circuits terminate on the same router at the ISP. We have BGP in place for load balancing and failover. I am changing out one of the two circuits so that I'll have diverse routes into my core, so looking forward the two circuits will still terminate on the same single router on my end but will terminate on two different routers at the ISP in different cities. The ISP is telling me they can no longer offer me BGP as a load balancing solution. What options do I have to ensure I have load balancing and failover (if one of the two circuits fail) of these circuits?
 
you are not truely multihoming so BGP is not necessary (in this config or the previous one). you can simply add two static default routes and the 3845 will do per-destination load balancing by default. what about the single point of failure that is the 3845?? what device is performing NAT??

 
Thanks unclerico. NAT is performed at our ASA. Yes, the single 3845 is a known single point of failure. I like your statment 'you can simply add two static default routes and the 3845 will do per-destination load balancing by default'. However, does that only provide load balancing, or failover as well?
 
i have a similar problem with failover on a 3825. how would i get the circuit to failover (no need for any loadbalancing). i've attempted to use 2 statics with one higher metric and also applied a route-map with as prepending but as soon i test by shutting down my prinary interface i lose all routing. any ideas most welcome.
 
you say you have floating static routes, but then you say you are doing as-prepending; so are you running BGP? post a scrubbed config...

 
I use SLA's for my failover and it works like a charm. I use it to fail over to a wireless cradlepoint when the active primary circuit goes down.
 
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