In This Lesson We Will
- Learn basic configuration of Cisco Routers
- Learn CLI Syntax for Routers
- IP Addressing Troubleshooting
Setting Up Your Cisco Router
Unlike switches, which are basically plug-n-play, routers do require a bit more configuration before being deployed into a network. These basic configuration tasks are listed below:
- Name the router
- Set a password
- Configure interfaces
- Save the changes/configurations
- Verify routing operations
Below is a screenshot of the commands used to set up a Cisco Router in PacketTracer:
Setting a name and password for the Router:
Not shown, you would save the configuration using command ‘copy running-config startup-config’
It’s worth noting that most of these commands are share with Cisco switches as well. For example, getting into Privilaged mode is still ‘enable’ and naming the device is still ‘hostname.’
To verify your configuration settings, use the command ‘show running-config’. An example of a ‘show running-config’ read out is below, not all info is shown as this is often a large readout.
You can also use ‘show ip interface brief’ to show the IP address, line status, and protocol status of all interfaces on the router. Below is an example of a ‘show ip interface brief’ command.
Configuring IPv6 on a Router
Enabling IPv6 on a router is relatively simple, using command ‘ipv6 unicast-routing’ in the global configuration mode will allow the router to begin listening for and responding to ND (neighbor discovery) on all active IPv6 interfaces. To add an IPv6 address to one of a routers interfaces, you have one of the following options:
- Configure the interface as an DHCPv6 client (meaning allowing a DHCPv6 server to automatically allocate and assign an IPv6 address for the interface)
- Configure a static IPv6 address using either the EUI-64 method of addressing:
- ‘ipv6 address ipv6-prefix/prefix-length eui-64′
- Or the full IPv6 address:
- ‘ipv6 address ipv6-address/prefix-length’
An interface can also remain unnumbered. This will be touched on in depth in the IPv6 lesson.
Troubleshoot Network Connectivity for IPv4 and IPv6
On any Windows device, open a command prompt terminal and type ‘ipconfig’ to show a readout of your local devices IP addresses (IPv4 and IPv6), as well as your default gateway. To show your DNS server and other information, type ‘ipconfig /all’. If your local device shows an IP address of 169.254.1.1, this generally means that you are not connected the internet, or are experiencing a DHCP issue.
Issuing a ‘ping’ command from the terminal will let you know if you are able to reach various parts of a network. For instance, to ensure you can reach another device in your network, let’s assume your IP address is active and your device is 10.0.0.2. Issue ‘ping 10.0.0.3’ to to determine if you can reach another device in your network. Assume your default gateway is 10.0.0.1. Issue ‘ping 10.0.0.1’ to determine if you can reach your default gateway. If the prior two pings are successful, your network is active. One last check is to determine if you reach the internet. Issue ‘ping 18.104.22.168’ to reach Googles DNS servers. If this ping succeeds, your network is up and has internet connectivity. If either of these pings fail, you know where the failure is located in your network topology by determining at which it fails at.