CCNA Notes
CompTIA LX103
Cisco ICND1
Cisco ICND2
Cisco CCNP Route
Various
Labs
CompTIA LX103
Cisco ICND1
Cisco ICND2
Cisco CCNP Route
Various
Labs
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Generic Routing Encapsulation protocol can be used as logical point-to-point links, encapsulating most any traffic over a tunnel as unicast. The unicast feature being useful over IPSEC as IPSEC only works over unicast traffic.
Assuming all destinations are routable
– creating a basic GRE Tunnel
over the following topology:
Simple Topology–
R1–
R1#conf t Enter configuration commands, one per line. End with CNTL/Z. R1(config)#int tunnel 100 R1(config-if)#tunnel source loopback 0 R1(config-if)#tunnel destination 10.35.0.1 *Mar 1 00:01:05.803: %LINEPROTO-5-UPDOWN: Line protocol on Interface Tunnel100, changed state to up
R3–
R3#conf t Enter configuration commands, one per line. End with CNTL/Z. R3(config)#interface tunnel 100 R3(config-if)#ip address 172.16.0.2 255.255.255.252 R3(config-if)#tunnel source loopback 0 R3(config-if)#tunnel destination 10.15.0.1 *Mar 1 00:12:56.219: %LINEPROTO-5-UPDOWN: Line protocol on Interface Tunnel100, changed state to up
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