300-410 Leak Questions

vty 0:

+ cisco

+ 0csic

vty 1:

+ no username

+ no password

The command “aaa authentication login default none” means no authentication is required when

access to the device via Console/VTY/AUX so if one interface does not specify another login

authentication method (via the “login authentication …” command), it will allow to access

without requiring username or password. In this case VTY 1 does not specify another

authentication login method so it will use the default method (which is “none” in this case).

The reason for the loop is that R2 is forwarding the packets destined to 10.1.1.1 to R4, instead of R1. This is because in the redistribute OSPF statement, BW metric has a higher value and delay has a value of 1. So, R2 chooses R4 over R1 for 10.1.1.0/24 subnet causing a loop. Now, R5 learns 10.1.1.0/24 from R3 and advertises the same route to R4, that R4 redistributes back in EIGRP. If R3 sets a tag of 1 while redistributing EIGRP in OSPF, and R4 denies all the OSPF routes with tag 1 while redistributing, it will not advertise 10.1.1.0/24 back into EIGRP. Hence, the loop will be broken.