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GRE? y or ynot?

I have an IPSec tunnel between two routers, and I was told I could use GRE. why or why wouldn't I want to use GRE? Thanks!!

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Re: GRE? y or ynot?

You dont need to use a GRE tunnel always...In some cases, where you need to run a routing protocol such as OSPF or EIGRP (which sends multicast packets) over the IPSEC connection. SInce IPSEC doesnt support multicast packets, you will need to run the protocol over a GRE tunnel, (create tunnel, run OSPF/EIGRP over tunnel interface), and then encrypt GRE traffic.

New Member

Re: GRE? y or ynot?

i was wondering if you had ever come across this problem before. i have two routers with an ipsec tunnel between them each router is running nat. one of the routers, router A has a static mapping of port 80 to an internal webserver. here is where i find a problem. a host on the internet trying to access the website through port 80 can. but a host on the remote site RouterB trying to access the local ip on the webserver through port 80 cannot. but if i take off the static mapping then they can. a friend of miine said running gre might take care of it because you get a tunnel interface seperate from the nat interface. but i'm wondering is there a way around this problem with running GRE? thanks!

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