Internet Access Failover design

[BHPCI_2]

We are installing a redundant internet connection and I would like some input on design consideration.  In the the attached image, the Internet 1 side is already in place.  We are in the process of getting the second 100MB Ethernet connection in place with the 3845 router.  These are diverse path loops with seperate public IP networks on the internal and external inerfaces of the routers.  Internet and VPN traffic will be on connection 1 and replication traffic will be on 2.  What would be the best way to provide failover between the two internet connections should one fail?

[ironshoreit]

Based on your design you will have issue with inbound traffic for publicly hosted services.   You best bet is to get a minimum /24 block of IP addresses from one of the providers and setup BGP.  Failover will occur with in maximum of 90Secs( BGP Hold Down Timer)    In order to set this up you will need to apply for a ASN number from ARIN unless you already have one. 

I run a similar setup at my company and we have taken hits with minimal downtime. 

[ironshoreit]

I forgot to mention you will need to run HSRP between the 2 ISP Edge routers once you get the /24 address.