CCNA commands

Command to get to privileged Exec mode

• Enable

Command to get to global config mode

• conf t

command to view available commands

• ?

command to view all commands that start with show

• show?

command to set a password

• enable password

command to see running-config

• show running-config

command to save running-config

• write

command to hide your password enable

• service password-encryption

create a more secure password

• Enable secret password

command to execute privileged exec commands from global config

• do

command to cancel or delete command

• no

  • no service password-encryption

command to view arp table

• arp -a

command to test reachability

• ping ip-address

command to view Mac address table

• show mac address-table

command to manually remove MAC addresses from table

• clear MAC address-table dynamic

command to manually remove specific Mac address from table

• clear Mac address-table dynamic ffff.ffff.fff

command to clear Mac address from table by the interface

• clear Mac address-table dynamic intG0/0

command to check status of each interface as well as their IP-addresses
(check after setting ip address to)

• show ip interface brief

get access to interface

• conf t

• int g0/0

set the ip-address

• conf t

• int g0/0

• ip address 10.255.255.254 255.0.0.0

• no shutdown

set ip address 10.255.255.254 on /8 subnet on interface g0/0

Then check to make sure it’s set properly

• en

• conf t

• int g0/0

• ip address 10.255.255.254 255.0.0.0

• no shutdown

• Do sh ip int br

command to get Mac address of an interface

• show interfaces g0/0

• hardware line has BIA or Mac-address

command to show all interfaces on a router and their l1/l2 status

• show interfaces description

Command to check switch interfaces
-It shows VLAN, duplex, speed, type

show interfaces status

command to shut down multiple interfaces on switch f0/5-12 interfaces

• int range f0/5-12

• description ## Not in use

• shutdown

command to view the routing table

show ip route

Command to configure static route

• ip route destinationip-address netmask next hop

• EX: ip route 192.168.13.3 255.255.255.0 192.168.13.254

Check the routing table after setting a static route to 192.168.13.3 /24 with a next hop of 192.168.13.254

• ip route 192.168.13.3 255.255.255.0 192.168.13.254

• do show ip route

the route in ip route is to

the destination route… net mask then the next-hop

Configure a static route, specifying the exit-interface:R1(config)# [...]

ip route ip-address netmask exit-interface

Configure a static route, specifying the exit-interface and next-hop IP:
R1(config)# [...]

ip route ip-address netmask exit-interface next-hop

Configure a default route, specifying the next-hop IP:
R1(config)# [...]

ip route 0.0.0.0 0.0.0.0 next-hop

a command used to verify that the IPv4 interfaces are up and up

show ip interface brief

release and renew address and flush dns

• ipconfig /release

• ipconfig /renew

  • ipconfig /flushdns

Practice Subnetting questions

k

practice VSLM subnetting questions

k

See which Vlan’s exist on a switch

• Show vlan brief

command to assign interfaces to a vlan

• interface range g0/1-3

• switchport mode access

• switchport access vlan 10

switchports which carry a single vlan are called
switchports which carry multiple are called

• access → one VLAN

• Trunk → multiple VLAN

name the vlan 10 to engineering

• do show vlan brief

• vlan 10

• name ENGINEERING

Set a switch to trunk and doublecheck it

• int g0/0

• switchport trunk encapsulation dot1q

• switchport mode trunk

• show interfaces trunk

check a switch trunk’s status

show interfaces trunk

configure vlan’s 10 and 30 on the trunk switch

switchport trunk allowed vlan 10,30

switch is in trunk mode and has VLAN 10,30 allowed… also put vlan 40 on there

• switchport trunk allowed vlan add 40

• do show interfaces trunk

remove vlan 40 on a trunk switch

• switchport trunk allowed vlan remove 40

For security purposes it is best to change the native vlan to

an unused VLAN

change the native vlan to 1001

switchport trunk native vlan 1001

the show vlan brief command

• shows _ assigned to each vlan

• access ports

  • use show interfaces trunk to confirm trunk ports

set a switch to trunk and vlan 10,30, set the native vlan to 1001

• switchport trunk encapsulation dot1q

• switchport mode trunk

• switchport allowed vlan 10,30

• switchport trunk native vlan 1001

• do show interfaces trunk

set up ROAS on interface g0/0

• int g0/0

• no shutdown

• interface g0/.10

• encapsulation dot1q 10

• ip address 192.168.1.62 255.255.255.192

when setting up ROAS interface g0/.10

the next command is

encapsulation dot1q #

the number represents

the vlan number

2 commands to configure native vlan on router

• encapsulation dot1q vlan-id native

  • configure the ip-address for the native vlan on the physical interface of the router

set a native VLAN on a router int g0/.10 vlan 10

• int g0/.10

• encapsulation dot1q 10 native

when using multilayer switch

configure it to send it to the switches SVI (as the default gateway) and not the default gateway on router

reset an interface to it’s default settings

• default interface g0/0

  • do show ip interface brief

set up a layer 3 switch to be multilayer

• ip routing

• interface g0/0

• no switchport

• ip address 192.168.1.30 255.255.255.192

set up a default route

• ip route 0.0.0.0 0.0.0.0 next-hop

confirm a layer 3 switch is routing

• show interfaces status

• show ip interface brief

configure an SVI on a layer 3 switch

• interface vlan10

• ip address 192.168.1.30 255.255.255.192

• no shutdown

command to show if a switch is set to access, auto or trunk

show interfaces g0/0 switchport

disable DTP on an interface

switchport nonegotiate

set switchport to use DTP

switchport mode ?
-(desirable, auto, access)

-switchport mode dynamic desirable

-switchport mode dynamic auto
-switchport mode access

switches that support both 802.1q and ISL you have to

switchport trunk encapsulate negotiate

get VTP information

show vtp status

change VTP name

VTP domain name

set switch to client mode in VTP

VTP mode client

Set switch to transparent mode

VTP mode transparent

put switch in server vtp mode

vtp mode server

check VTP

show VTP status

change vtp version

vtp version

command to check which port is designated, non designated(blocked), etc etc

show spanning-tree

spanning tree operates by ___ even without configuration

default

(also switches in trunk don;t work for that shit.. portfast is only for access)

put spanning tree in pordtfast mode

• int g0/2

• spanning-tree portfast

command to protect portfast

• spanning-tree bpduguard enable

enable bpdu guard by default

spanning-tree portfast bpduguard default

enable a port that was disabled by bpduguard

• int g0/0

• shutdown

• no shutdown

configure spanning tree mode

• spanning-tree mode ?

configure root bridge

• spanning-tree vlan 1 root primary

• do show spanning-tree

set secondary root bridge

• spanning-tree vlan 1 root secondary

configure spanning-tree cost or priority

spanning-tree vlan 1 ?

• cost 200

• port-priority 32

configure a point to point connection in ST

spanning-tree link-type point-to-point

configure a shared connection in ST

spanning-tree link-type shared

check load balancing on etherchannel

show etherchannel load-balance

configure etherchannel load balancing method and check it

• port-channel load-balance ?

• do show etherchannel load-balance

PAGP configuration

• int range

• channel-group 1 mode ?

in Etherchannel they must have matching

• same duplex

• same speed

• same switchport mode

  • same allowed VLAN/Native vlan(for trunk)

check status of etherchannel

• show etherchannel summary

• show etherchannel port-channel

check etherchannel mode it’s in

• show etherchannel port-channel

configure layer 3 etherchannel

• int range g0/0 - 3

• no switchport

• channel-group 1 mode active

• show running-config

• int p01

• ip address 10.0.0.0 255.255.255.0

check the switchport operational mode

do show interface g0/1 switchport

configure a static route and change the AD

ip route 10.0.0.0 255.255.255.192 100

go into RIP

• router rip

• version 2

• no auto-summary

• Network ip-address

• Network ip-address

Network automatically converts It and no need to convert network mask

on EIGRP or rip routers end hosts should be configured as (anything without rip neighbors should)

• passive-interface g2/0

share the default gateway route into rip

• default-information originate

command to check rip, eigrp, ospf

• show ip protocols

in RIP (Routing Information Protocol) is a command used in network devices to configure how many equal-cost routes to the same destination can be installed in the routing table for load balancing

maximum-paths #

Command to change AD (admin distance) a local measure of trustworthiness (lower is better) used to pick the best path when multiple protocols offer routes to the same network

distance ?

EIGRP basic configurations

• router eigrp #

• no auto-summary

• Network 10.0.0.0

• network 172.16.1.0 0.0.0.15

it’s router EIGRP # (the number is for Autonomous system number)

on EIGRP the router EIGRP # (AS number) must

match between routers

manually configure EIGRP router id

eigrp router-id ?