GRE Tunneling on Cisco IOS – Destination Address

cisco-iosgretunnel

What is the reason that you cannot set the tunnel's other side as destination address? Is this because it is virtual only?

192.168.1.0/30 is the subnet I'm using and this is my configuration:

tunnel1
ip add 192.168.1.1 255.255.255.252
tunnel source (doesn't matter)
tunnel dest 192.168.1.2

tunnel dest 192.168.1.2 -> Why is this invalid?

Best Answer

Yes,

The tunnels IP addresses need to be on their own subnet. The tunnel source and destination identify the points on the network where routers should encapsulate or de-encapsulate the traffic that is sent thru the tunnels. Having a route to your tunnel destination is a requirement for a tunnel interface to show "UP/UP" so really the 192.168.1.0/30 subnet doesn't even exist on the network until your source and destinations are configured.

Related Topic