Panasonic NN46240-710 - Manual (Page 59)

Nortel Secure Router 8000 Series
Troubleshooting - VPN___________ 2 GRE troubleshooting
Item Subitem Notes
Specifying the
source address of
the tunnel
Source The source address of a tunnel is the IP address of the
physical interface that sends the GRE packets.
The source address of a tunnel can be
• Source interface
• IP address of the source interface
• Another tunnel interface
Specifying the
destination
address of the
tunnel
Destination The destination address of the tunnel is the IP address
of the interface that receives GRE packets.
You must specify the destination address as the IP
address of the destination end.
The source address and the destination address
uniquely identify a tunnel. These configurations must
be performed on both ends of a tunnel.
Assigning an IP
address for the
tunnel interface
IP address If the tunnel supports dynamic routing protocols, you
must configure an IP address or configure
unnumbered IP addresses for the tunnel.
The IP address of the tunnel interface does not need to
be a public network address.
Configuring the
routes forwarded
by the tunnel
Static route or
dynamic route
The routes on both ends of a tunnel must use routes
that are forwarded by the tunnel to forward
GRE-encapsulated packets correctly. Configure static
or dynamic routes at both ends of the tunnel.
While you configure static routes, note that the
destination address is the address of the interface that
receives the packet without the GRE encapsulation.
The next hop is the address of the local tunnel
interface.
While you configure dynamic routes, you must enable
the dynamic protocol on both the tunnel interface and
the interface of the router that connects with the
private network. To ensure that the correct route is
chosen, do not choose the tunnel interface as the
outgoing interface.
Configuring the
GRE key
(optional)
GRE key If the GRE key is required, configure the key on both
ends and specify the same key-number.
Use Figure 2-3 as an example to describe the notes about configuring GRE.
# Configuring a tunnel interface on Nortel 1
# Assign an IP address for POS 1/0/0:
[Nortell] interface pos 1/0/0
[Nortel1-Pos1/0/0] ip address 100.1.1.1 255.255.255.0
# Assign an IP address for the tunnel interface:
Issue 5.3 (30 March 2009) Nortel Networks Inc. 2-5