Default Configuration

Updated: May 4, 2026

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Overview

Details the boot-up process, including how the device searches for configuration files, and provides procedures for configuring global parameters, interfaces (Gigabit Ethernet and Loopback), command-line access, and static/dynamic routing (RIP and EIGRP).

Default configuration indicates the tasks performed by the device during the boot up process.

When you boot up the device in autonomous mode, the device looks for a file named c8000.cfg in the bootflash. If the file is not found in the bootflash, the device then looks for ciscortr.cfg file. If none of the files are found, the device then checks for any inserted USB that may have stored these files in the same particular order.

If there is a configuration file with the PID as its name in an inserted USB, but one of the standard files are in bootflash, the system finds the standard file for use.

Configure Global Parameters

Global parameters refer to configuration settings that apply to the entire router, influencing its overall operation and behavior rather than being specific to a single interface or feature. To manually define Gigabit Ethernet interfaces, follow these steps, beginning from global configuration mode.

Procedure

	1.	configure terminal Example: `Router> enable Router# configure terminal Router(config)#` Enters global configuration mode when using the console port. Use the following to connect to the device with a remote terminal: `telnet router-name or address Login: login-id Password: ********* Router> enable`
	2.	hostname name Example: `Router(config)# hostname Router` Specifies the name for the device.
	3.	enable secret password Example: `Router(config)# enable secret cr1ny5ho` Specifies an encrypted password to prevent unauthorized access to the device.
	4.	no ip domain-lookup Example: `Router(config)# no ip domain-lookup` Disables the device from translating unfamiliar words (typos) into IP addresses.

Configure Gigabit Ethernet Interfaces

A Gigabit Ethernet Interface is a physical network interface used to connect devices in a local area network (LAN) for significantly improved throughput.To manually configure Gigabit Ethernet interfaces, follow these steps, beginning from global configuration mode.

Procedure

	1.	interface gigabitethernet slot/bay/port Example: `Router(config)# interface gigabitethernet 0/0/1` Enters the configuration mode for a Gigabit Ethernet interface on the device.
	2.	ip address ip-address mask Example: `Router(config-if)# ip address 192.0.2.2 255.255.255.0` Sets the IP address and subnet mask for the specified Gigabit Ethernet interface. Use this Step if you are configuring an IPv4 address.
	3.	ipv6 address ipv6-address/prefix Example: `Router(config-if)# ipv6 address 2001.db8::ffff:1/128` Sets the IPv6 address and prefix for the specified Gigabit Ethernet interface. Use this step instead of Step 2, if you are configuring an IPv6 address.
	4.	no shutdown Example: `Router(config-if)# no shutdown` Enables the Gigabit Ethernet interface and changes its state from administratively down to administratively up.
	5.	exit Example: `Router(config-if)# exit` Exits configuration mode for the Gigabit Ethernet interface and returns to privileged EXEC mode.

Configure a Loopback Interface

A loopback interface is a virtual network interface that is implemented entirely in software and is not associated with any physical hardware. It allows a device to send and receive data packets to itself, facilitating internal communication and diagnostics without involving external network components.This task explains how to configure a loopback interface.

Procedure

	1.	interface type number Example: `Router(config)# interface Loopback 0` Enters configuration mode on the loopback interface.
	2.	(Option 1) ip address ip-address mask Example: `Router(config-if)# ip address 10.108.1.1 255.255.255.0` Sets the IP address and subnet mask on the loopback interface. (If you are configuring an IPv6 address, use the ipv6 address command.
	3.	(Option 2) ipv6 address ipv6-address/prefix Example: `Router(config-if)# 2001:db8::ffff:1/128` Sets the IPv6 address and prefix on the loopback interface.
	4.	exit Example: `Router(config-if)# exit` Exits configuration mode for the loopback interface and returns to global configuration mode.

Verifying Loopback Interface Configuration

This configuration example shows the loopback interface configured on the Gigabit Ethernet interface with an IP address of 203.0.113.1/32, which acts as a static IP address. The loopback interface points back to virtual-template1, which has a negotiated IP address.


				!
				interface loopback 0
				ip address 203.0.113.1 255.255.255.255 (
				static IP address
				)
				ip nat outside
				!
				interface Virtual-Template1
				ip unnumbered loopback0
				no ip directed-broadcast
				ip nat outside

Enter the show interface loopback command. You should see an output similar to the following example:


				Router# 
				show interface loopback 0
				Loopback0 is up, line protocol is up 
				Hardware is Loopback
				Internet address is 203.0.113.1/32
				MTU 1514 bytes, BW 8000000 Kbit/sec, DLY 5000 usec, 
				reliability 255/255, txload 1/255, rxload 1/255
				Encapsulation LOOPBACK, loopback not set
				Keepalive set (10 sec)
				Last input never, output never, output hang never
				Last clearing of "show interface" counters never
				Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
				Queueing strategy: fifo
				Output queue: 0/0 (size/max)
				5 minute input rate 0 bits/sec, 0 packets/sec
				5 minute output rate 0 bits/sec, 0 packets/sec
				0 packets input, 0 bytes, 0 no buffer
				Received 0 broadcasts (0 IP multicasts)
				0 runts, 0 giants, 0 throttles 
				0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort
				0 packets output, 0 bytes, 0 underruns
				Output 0 broadcasts (0 IP multicasts)
				0 output errors, 0 collisions, 0 interface resets
				0 output buffer failures, 0 output buffers swapped out

Alternatively, use the ping command to verify the loopback interface, as shown in the following example:


				Router# 
				ping  203.0.113.1
				Type escape sequence to abort.
				Sending 5, 100-byte ICMP Echos to 203.0.113.1, timeout is 2 seconds:
				!!!!!
				Success rate is 100 percent (5/5), round-trip min/avg/max = 1/1/1 ms

Dynamic Allocation of Cores

Dynamic allocation of cores provide flexibility for users to leverage the CPU cores for different services or for CEF/IPSec performances. The Catalyst 8000 Series Edge platforms are equipped with a minimum of eight CPU cores and have the flexibility to allocate cores into the service plane from the data plane. The core allocation is based on the customer configuration of the different services available on these platforms.

From Cisco IOS XE Release 17.4 onwards, you can use the platform resource { service-plane-heavy | data-plane-heavy } command to adjust the cores across service plane and data plane. However, you have to reboot the device for the configured profile to take effect.

These are the list of Catalyst 8000 Series Edge platforms that support changing the core allocations dynamically:

C8300-2N1S-6T
C8300-2N1S-4T2X
C8300-2N2S-6T
C8300-2N2S-4T2X
C8200-1N-4T

Configure Command-Line Access

Command-line access refers to the method of interacting with the device's operating system through a text-based interface known as the Command-Line Interface (CLI). This interface allows users to enter commands directly to configure, manage, and troubleshoot the device. The CLI in Cisco IOS XE provides a powerful and flexible way to control the device, supporting a wide range of commands for various functions. To configure parameters to control access to the device, use these steps :

Procedure

	1.	line [ \| console \| tty \| vty ] line-number Example: `Router(config)#line console 0` Enters line configuration mode, and specifies the type of line. The example provided here specifies a console terminal for access.
	2.	password password Example: `Router(config-line)#password 5dr4Hepw3` Specifies a unique password for the console terminal line.
	3.	login Example: `Router(config-line)#login` Enables password checking at terminal session login.
	4.	exec-timeout minutes [ seconds ] Example: `Router(config-line)# exec-timeout 5 30 Router(config-line)#` Sets the interval during which the EXEC command interpreter waits until user input is detected. The default is 10 minutes. Optionally, adds seconds to the interval value. The example provided here shows a timeout of 5 minutes and 30 seconds. Entering a timeout of 0 0 specifies never to time out.
	5.	exit Example: `Router(config-line)#exit` Exits line configuration mode to re-enter global configuration mode.
	6.	line [ \| console \| tty \| vty ] line-number Example: `Router(config)# line vty 0 4 Router(config-line)#` Specifies a virtual terminal for remote console access.
	7.	password`password` Example: `Router(config-line)#password aldf2ad1` Specifies a unique password for the virtual terminal line.
	8.	login Example: `Router(config-line)#login` Enables password checking at the virtual terminal session login.
	9.	end Example: `Router(config-line)#end` Exits line configuration mode, and returns to privileged EXEC mode.

This configuration shows the command-line access commands.

You do not have to input the commands marked default. These commands appear automatically in the configuration file that is generated when you use the show running-config command.


!
line console 0
exec-timeout 10 0
password 4youreyesonly
login
transport input none (

 default
)
stopbits 1 (

 default
)
line vty 0 4
password secret
login
!

Configure static routes

Static routes provide fixed routing paths through the network. They are manually configured on the device. If the network topology changes, the static route must be updated with a new route. Static routes are private routes unless they are redistributed by a routing protocol .

To configure static routes, follow these steps :

Procedure

	1.	(Option 1) ip route prefix mask {ip-address \| interface-type interface-number [ip-address]} Example: `Router(config)# ip route 192.0.2.8 255.255.0.0 10.10.10.2` Specifies a static route for the IP packets. (If you are configuring an IPv6 address, use the ipv6 route command described below.)
	2.	(Option 2) ipv6 route prefix/mask {ipv6-address \| interface-type interface-number [ipv6-address]} Example: `Router(config)# ipv6 route 2001:db8:2::/64 2001:DB8:3000:1` Specifies a static route for the IP packets.
	3.	end Example: `Router(config)# end` Exits global configuration mode and enters privileged EXEC mode.

Dynamic routes

In dynamic routing, the network protocol adjusts the path automatically, based on network traffic or topology. Changes in dynamic routes are shared with other devices in the network.

A device can use IP routing protocols, such as Routing Information Protocol (RIP) or Enhanced Interior Gateway Routing Protocol (EIGRP), to learn about routes dynamically.

Configure Routing Information Protocol

This task covers details on configuring Routing Information Protocol that helps routers determine the most efficient path for data packets to travel across a network.

Procedure

	1.	router rip Example: `Router(config)# router rip` Enters router configuration mode, and enables RIP on the router.
	2.	version { 1 \| 2 } Example: `Router(config-router)# version 2` Specifies use of RIP version 1 or 2.
	3.	network ip-address Example: `Router(config-router)# network 192.0.2.8 Router(config-router)# network 10.10.7.1` Specifies a list of networks on which RIP is to be applied, using the address of the network of each directly connected network.
	4.	no auto-summary Example: `Router(config-router)# no auto-summary` Disables automatic summarization of subnet routes into network-level routes. This allows subprefix routing information to pass across classful network boundaries.
	5.	end Example: `Router(config-router)# end` Exits router configuration mode, and enters privileged EXEC mode.

This completes the configuration of Routing Information Protocol.

What to do next

Verify the Routing Information Protocol configuration is complete.

Use the show running-config command from privileged EXEC mode.


    !
    Router# 
    show running-config
    service timestamps debug datetime msec
    service timestamps log datetime msec
    service call-home
    platform qfp utilization monitor load 80
    platform punt-keepalive disable-kernel-core
    platform hardware throughput crypto 1G
    :
    :
    call-home
    ! If contact email address in call-home is configured as sch-smart-licensing@cisco.com
    ! the email address configured in Cisco Smart License Portal will be used as contact email address to send SCH notifications.
    contact-email-addr sch-smart-licensing@cisco.com
    profile "CiscoTAC-1"
    active
    destination transport-method http
    !
    !
    end

To verify that you have configured RIP correctly, enter the show ip route command and look for RIP routes marked with the letter R. You should see an output similar to the one shown in this example:


    Router# 
    show ip route
    Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
    D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
    N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
    E1 - OSPF external type 1, E2 - OSPF external type 2
    i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
    ia - IS-IS inter area, * - candidate default, U - per-user static route
    o - ODR, P - periodic downloaded static route
    Gateway of last resort is not set
    10.0.0.0/24 is subnetted, 1 subnets
    C       10.108.1.0 is directly connected, Loopback0
    R    192.0.2.3/8 [120/1] via 192.0.2.2, 00:00:02, Ethernet0/0/0

Configure Enhanced Interior Gateway Routing Protocol

This task covers details on configuring Enhanced Interior Gateway Routing Protocol. Enhanced Interior Gateway Routing Protocol (EIGRP) is an advanced distance-vector routing protocol designed to automate routing decisions and configuration within a computer network, facilitating the efficient and reliable exchange of routing information between routers.

Procedure

	1.	router eigrp as-number Example: `router eigrp 109` Enters router configuration mode, and enables EIGRP on the router. The autonomous-system number identifies the route to other EIGRP routers and is used to tag the EIGRP information
	2.	network ip-address Example: `Router(config)# network 192.0.2.8 Router(config)# network 10.10.12.15` Specifies a list of networks on which EIGRP is to be applied, using the IP address of the network of directly connected networks.
	3.	end Example: `Router(config-router)# end` Exits router configuration mode, and enters privileged EXEC mode.

This completes the configuration of EIGRP.

What to do next

Verify that EIGRP configuration is complete:

This configuration example shows the EIGRP routing protocol enabled in IP networks 192.0.2.8 and 10.10.12.15. The EIGRP autonomous system number is 109. To see this configuration, use the show running-config command.

Router# show running-config

router eigrp 109
network 192.0.2.8
network 10.10.12.15

To verify that you have configured IP EIGRP correctly, enter the show ip route command, and look for EIGRP routes marked by the letter D. You should see verification output similar to the following:

Router# show ip route
Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route

Gateway of last resort is not set

10.0.0.0/24 is subnetted, 1 subnets
C       10.108.1.0 is directly connected, Loopback0
D    	192.0.2.3/8 [90/409600] via 192.0.2.2, 00:00:02, Ethernet0/0

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Default Configuration

Overview

Configure Global Parameters

Procedure

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Configure Gigabit Ethernet Interfaces

Procedure

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Configure a Loopback Interface

Procedure

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Verifying Loopback Interface Configuration

Dynamic Allocation of Cores

Configure Command-Line Access

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Configure static routes

Procedure

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Dynamic routes

Configure Routing Information Protocol

Procedure

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What to do next

Configure Enhanced Interior Gateway Routing Protocol

Procedure

Example:

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What to do next