R1#show ip route
10.0.0.0/24 is subnetted, 3 subnets
C 10.1.13.0 is directly connected, Serial0/0
C 10.1.1.0 is directly connected, Loopback0
C 10.1.146.0 is directly connected, FastEthernet0/0
* I have two directly connected network and one Loopback.
* The network 10.1.146.0/24 is network between R1&R4&R6.
# Make ping
R1#ping 10.1.146.6
Sending 5, 100-byte ICMP Echos to 10.1.146.6, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 8/20/52 ms
R1#ping 10.1.146.4
Sending 5, 100-byte ICMP Echos to 10.1.146.4, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 16/22/32 ms
* When I make ping and this ping is successful it´s says 3 things are correctly configured:
1) Routing lookup process is correct
2) Switching mechanism is moving packets out the interface
3) Encapsulation is correctly configured
R1#show ip route 10.1.146.6
Routing entry for 10.1.146.0/24
Known via "connected", distance 0, metric 0 (connected, via interface)
Routing Descriptor Blocks:
* directly connected, via FastEthernet0/0 <---- We know where we have to send.
Route metric is 0, traffic share count is 1
R1#show ip cef exact-route 10.1.146.1 10.1.146.4
10.1.146.1 -> 10.1.146.4 : FastEthernet0/0 (next hop 10.1.146.4) <-- we ned to know mak address.
R1#show arp
Protocol Address Age (min) Hardware Addr Type Interface
Internet 10.1.146.1 - c201.0d08.0000 ARPA FastEthernet0/0
Internet 10.1.146.4 32 c200.0d08.0000 ARPA FastEthernet0/0 <--- MAC Address
Internet 10.1.146.6 32 c205.1488.0000 ARPA FastEthernet0/0
* Now we know how to forward traffic out the interface.
* If no one filtering ARPs we have basic connectivity.
#Configure incorrect ARP entry.
R1(config)#arp 10.1.146.4 aaaa.aaaa.aaa4 arpa
R1#show arp
Protocol Address Age (min) Hardware Addr Type Interface
Internet 10.1.146.1 - c201.0d08.0000 ARPA FastEthernet0/0
Internet 10.1.146.4 - aaaa.aaaa.aaa4 ARPA <--- Static ARP entry
Internet 10.1.146.6 41 c205.1488.0000 ARPA FastEthernet0/0
R1#ping 10.1.146.4
Sending 5, 100-byte ICMP Echos to 10.1.146.4, timeout is 2 seconds:
.....
Success rate is 0 percent (0/5)
* The connectivity filed.
# Configure Route to reach Lo 0 of R4
R1(config)#ip route 10.1.4.0 255.255.255.0 10.1.146.4
R1#ping 10.1.4.4
Sending 5, 100-byte ICMP Echos to 10.1.4.4, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 20/25/32 ms
R1#show ip cef exact-route 10.1.146.1 10.1.4.4
10.1.146.1 -> 10.1.4.4 : FastEthernet0/0 (next hop 10.1.146.4)
R1#show ip route static
10.0.0.0/24 is subnetted, 4 subnets
S 10.1.4.0 [1/0] via 10.1.146.4
* Now I have to know how to reach 10.1.146.4
R1#show ip route 10.1.146.4
Routing entry for 10.1.146.0/24
Known via "connected", distance 0, metric 0 (connected, via interface)
Routing Descriptor Blocks:
* directly connected, via FastEthernet0/0
Route metric is 0, traffic share count is 1
# Configure Incorrect more specific route.
R1(config)#ip route 10.1.146.4 255.255.255.255 serial 0/0
R1(config)#do ping 10.1.146.4
Sending 5, 100-byte ICMP Echos to 10.1.146.4, timeout is 2 seconds:
UUUUU
Success rate is 0 percent (0/5)
* The connectivity filed.
# Debug
R1(config)#do debug ip icmp
ICMP packet debugging is on
R1(config)#do ping 10.1.146.4
Sending 5, 100-byte ICMP Echos to 10.1.146.4, timeout is 2 seconds:
UUUUU
Success rate is 0 percent (0/5)
*Mar 1 01:38:04.599: ICMP: dst (10.1.13.1) host unreachable rcv from 10.1.13.3
*Mar 1 01:38:04.627: ICMP: dst (10.1.13.1) host unreachable rcv from 10.1.13.3
*Mar 1 01:38:04.635: ICMP: dst (10.1.13.1) host unreachable rcv from 10.1.13.3
*Mar 1 01:38:04.635: ICMP: dst (10.1.13.1) host unreachable rcv from 10.1.13.3
*Mar 1 01:38:04.639: ICMP: dst (10.1.13.1) host unreachable rcv from 10.1.13.3
* Its says that R3 doesn't have destination route.
#Configure incorrect out interface.
R1(config)#ip route 10.1.4.4 255.255.255.255 ser0/0 10.1.146.4
R1#show ip route 10.1.4.4
Routing entry for 10.1.4.4/32
Known via "static", distance 1, metric 0
Routing Descriptor Blocks:
* 10.1.146.4, via Serial0/0 <--- incorrect out interface
Route metric is 0, traffic share count is 1
