Configuring Gre Tunneling; Gre Tunneling Overview - Avaya G250 Administration

Use the show ip route command to display information about the IP routing table.
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Use the show ip route best-match command, followed by an IP address, to display
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a routing table for a destination address.
Use the show ip route static command to display static routes.
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Use the show ip route summary command to display the number of routes known to
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the device.
Use the traceroute command, followed by an IP address, to trace the route an IP
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packet would follow to the specified IP address. The G250/G350 traces the route by
launching UDP probe packets with a small time to live (TTL), then listening for an ICMP
time exceeded reply from a gateway.

Configuring GRE tunneling

This section provides information about configuring GRE tunnels and contains the following
topics:

GRE tunneling overview

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Setting up a GRE tunnel
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Routing packets to a GRE tunnel
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Preventing nested tunneling in GRE tunnels
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tunnels from causing loops
Optional GRE tunnel features
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GRE tunnels
Additional GRE tunnel parameters
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parameters
GRE tunnel application example
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GRE tunneling overview
Generic Routing Encapsulation (GRE) is a multi-carrier protocol that encapsulates packets with
an IP header and enables them to pass through the Internet via a GRE tunnel. A GRE tunnel is
a virtual interface in which two routers serve as endpoints. The first router encapsulates the
packet and sends it over the Internet to a router at the far end of the GRE tunnel. The second
router removes the encapsulation and sends the packet towards its destination.
A GRE tunnel is set up as an IP interface, which allows you to use the GRE tunnel as a routing
destination. A GRE tunnel can transport multicast packets, which allows it to work with routing
protocols such as RIP and OSPF.
— an overview of GRE tunneling
— instructions on how to configure a GRE tunnel
— instructions on how to route packets to a GRE tunnel
— instructions on how to prevent GRE
— a description of optional features you can configure on
— a list and description of additional GRE tunnel
— a sample application for GRE tunneling
Configuring GRE tunneling
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