Cisco 1801, Configuration Manual

Page: 95 / 198

7-9
Cisco 1800 Series Integrated Services Routers (Fixed) Software Configuration Guide
OL-6426-02
Chapter 7 Configuring VPNs Using an IPSec Tunnel and Generic Routing Encapsulation
Configure a GRE Tunnel
Step 3
tunnel source interface-type number
Example:
Router(config-if)# tunnel source
fastethernet 2
Router(config-if)#
Specifies the source endpoint of the router for the
GRE tunnel.
Step 4 tunnel destination default-gateway-ip-address
Example:
Router(config-if)# tunnel destination
192.168.101.1
Router(config-if)#
Specifies the destination endpoint of the router for
the GRE tunnel.
Step 5 crypto map map-name
Example:
Router(config-if)# crypto map static-map
Router(config-if)#
Assigns a crypto map to the tunnel.
Note
Dynamic routing or static routes to the
tunnel interface must be configured to
establish connectivity between the sites.
See the
Cisco IOS Security Configuration
Guide for details.
Step 6 exit
Example:
Router(config-if)# exit
Router(config)#
Exits interface configuration mode, and returns to
global configuration mode.
Step 7 ip access-list { standard | extended }
access-list-name
Example:
Router(config)# ip access-list extended
vpnstatic1
Router(config-acl)#
Enters ACL configuration mode for the named
ACL that is used by the crypto map.
Step 8 permit protocol source source-wildcard
destination destination-wildcard
Example:
Router(config-acl)# permit gre host
192.168.100.1 host 192.168.101.1
Router(config-acl)#
Specifies that only GRE traffic is permitted on the
outbound interface.
Step 9 exit
Example:
Router(config-acl)# exit
Router(config)#
Returns to global configuration mode.
Command or Action Purpose