BitWithBiteCCNA Networking · Quick Reference
Module 10 — Basic Router Configuration Cheat Sheet
In one line: A Cisco router, fresh out of the box or reset to factory defaults, has no configuration at all. Bringing it into a working network follows the same basic sequence every time — s...
Key Ideas
1Initial Router Configuration. A Cisco router, fresh out of the box or reset to factory defaults, has no configuration at all. Bringing it into a working network follows the same basic sequence ever...
2Configure Router Interfaces. A router does nothing useful until its interfaces are configured and enabled. Each routed interface needs an IP address and subnet mask, and must be turned on with no ...
3Verify Interface Configuration. After configuring interfaces, verification confirms everything is working as intended before moving on. Several show commands give different levels of detail — knowing...
4Configure the Default Gateway. A default gateway is the address a host or switch sends traffic to when the destination is on a different network. Without one, devices can only communicate within the...
5Connect a Router to a LAN. Putting it all together: a small topology with one router connecting a LAN switch to a WAN link demonstrates the full configuration workflow in one place.
Code Examples
! Enter global configuration mode
Router> enable
Router# configure terminal
! Set the hostname
Router(config)# hostname R1
! Secure privileged EXEC mode
R1(config)# enable secret Cisco12345
! Secure the console line
R1(config)# line console...
! Configure GigabitEthernet0/0 — LAN-facing interface
R1(config)# interface GigabitEthernet0/0
R1(config-if)# description LAN - Connects to SW1
R1(config-if)# ip address 192.168.1.1 255.255.255.0
R1(config-if)# ipv6 address 2001:db8:1::1/64
R1(config-i...
R1# show ip interface brief
Interface IP-Address OK? Method Status Protocol
GigabitEthernet0/0 192.168.1.1 YES manual up up
Serial0/0/0 203.0.113.1 YES manual up ...