I wonder if anyone can assist:
We are changing ISP, and for a short period have two lines, each with a 2811. We use NAT translating a number of IP addresses onto one internally addressed web server. Unfortunatly I can't transition all the sites to the new IP address range at the same time. This means I can't change the gateway address an the web server without cutting off half the web sites.
On the old ISP at least, BGP is out of the question.
It has been suggested that traffic coming down the old ISP line could be tunneled to the new router, but then default routes don't allow for the return route through the tunnel as far as I can see/
Is there a way to allow for NAT traffic via two lines and two routers to one server? I wonder if somhow nat outside can be used.
I'm sure this must be a fairly common issue! What is the best way to solve it?