Static routing mode
Networking requirements
Configuration steps
Configuring network interfaces
#############SwitchA##########################
SwitchA(config)# interface eth-0-1
SwitchA(config-if)# no switchport
SwitchA(config-if)# ip address 192.168.1.1/24
SwitchA(config-if)# exit
SwitchA(config)# interface eth-0-23
SwitchA(config-if)# no switchport
SwitchA(config-if)# ip address 10.1.1.1/24
SwitchA(config-if)# exit
SwitchA(config)#
#############SwitchB##########################
SwitchB(config)# interface eth-0-23
SwitchB(config-if)# no switchport
SwitchB(config-if)# ip address 10.1.1.2/24
SwitchB(config-if)# exit
SwitchB(config)# interface eth-0-24
SwitchB(config-if)# no switchport
SwitchB(config-if)# ip address 10.1.2.2/24
SwitchB(config-if)# exit
SwitchB(config)#
#############SwitchC##########################
SwitchC(config)# interface eth-0-24
SwitchC(config-if)# no switchport
SwitchC(config-if)# ip address 10.1.2.3/24
SwitchC(config-if)# exit
SwitchC(config)# interface eth-0-1
SwitchC(config-if)# no switchport
SwitchC(config-if)# ip address 192.168.2.1/24
SwitchC(config-if)# exit
SwitchC(config)#
Configure static routes to make the tunnel network reachable
#############SwitchA##########################
SwitchA(config)# ip route 10.1.2.0/24 10.1.1.2
SwitchA(config)#
#############SwitchC##########################
SwitchC(config)# ip route 10.1.1.0/24 10.1.2.2
SwitchC(config)#
Configure GRE Tunnel
#############SwitchA##########################
SwitchA(config)# interface eth-0-23
SwitchA(config-if)# tunnel enable
SwitchA(config-if)# exit
SwitchA(config)# interface tunnel 1
SwitchA(config-if)# tunnel mode gre
SwitchA(config-if)# tunnel source eth-0-23
SwitchA(config-if)# tunnel destination 10.1.2.3
SwitchA(config-if)# keepalive 5 3
SwitchA(config-if)# ip address 192.168.168.1/24
SwitchA(config-if)# exit
#############SwitchC##########################
SwitchC(config)# interface eth-0-24
SwitchC(config-if)# tunnel enable
SwitchC(config-if)# exit
SwitchC(config)# interface tunnel 1
SwitchC(config-if)# tunnel mode gre
SwitchC(config-if)# tunnel source eth-0-24
SwitchC(config-if)# tunnel destination 10.1.1.1
SwitchC(config-if)# keepalive 5 3
SwitchC(config-if)# ip address 192.168.168.2/24
SwitchC(config-if)# exit
Configure GRE tunnel routes
#############SwitchA##########################
SwitchA(config)# ip route 192.168.2.0/24 tunnel1
#############SwitchC##########################
SwitchC(config)# ip route 192.168.1.0/24 tunnel1
Result verification
Check tunnel status
SwitchA# show interface tunnel 1
Interface tunnel1
Interface current state: UP
Hardware is Tunnel
Index 8193 , Metric 1 , Encapsulation TUNNEL
VRF binding: not bound
Internet primary address:
192.168.168.1/24 pointopoint 192.168.168.255
Tunnel protocol/transport GRE/IP, Status Valid
Tunnel source 10.1.1.1(eth-0-23)
Tunnel destination 10.1.2.3
Tunnel DSCP inherit, Tunnel TTL 254
Tunnel GRE key disable
Tunnel GRE keepalive enable, Send period: 5, Retry times: 3
11882 packets input, 1253396 bytes
17259 packets output, 1734436 bytes
SwitchA#
Verify the tunnel is reachable
SwitchA# ping -a 192.168.168.1 192.168.168.2
PING 192.168.168.2 (192.168.168.2) from 192.168.168.1 : 56(84) bytes of data.
64 bytes from 192.168.168.2: icmp_seq=1 ttl=64 time=1.87 ms
64 bytes from 192.168.168.2: icmp_seq=2 ttl=64 time=1.61 ms
64 bytes from 192.168.168.2: icmp_seq=3 ttl=64 time=1.59 ms
64 bytes from 192.168.168.2: icmp_seq=4 ttl=64 time=1.52 ms
64 bytes from 192.168.168.2: icmp_seq=5 ttl=64 time=1.65 ms
— 192.168.168.2 ping statistics —
5 packets transmitted, 5 received, 0% packet loss, time 4006ms
rtt min/avg/max/mdev = 1.524/1.653/1.872/0.120 ms
SwitchA#
Network intercommunication
In this case, PC2 can be pinged from PC1. The test procedure is omitted.
