Router troubleshooting

In this section, you will get acquainted with some of the possible scenarios ofproblemsthat may occur in routers.

Verifying IPv4 interface settings

So far, we have seen that the show command accompanied by its relevant options is quite handy in identifying various issues on switch interfaces. In that line of discussion, we are interested to know how handy the show command would be in identifying issues on router interfaces. The following lists some of the show command variations that can be used to verify IPv4 interface settings:

• The show ip interface brief command shows some brief information about all the router's interfaces, including their IPv4 addresses (see Figure 8.5):

Figure 8.5. The show ip interface brief command in action

• The show ip route command shows the content of the IPv4 routing table stored in RAM (see Figure 8.6):

Figure 8.6. The show ip route command in action

• The show running-config interface <interface-id> command shows the commands configured...