Cisco Command - Cheat Sheet

A comprehensive reference guide for CISCO CCNA CLI commands, both basic and advanced.

Cisco Modes

Mode	Description
Router>	User mode
Router#	Privilege mode
Router(config)#	Global Config mode
Router(config-if)	Interface mode
Router(config-vlan)#	Vlan config mode
Router(config-router)#	router config mode

Basic Commands

Command	Purpose
enable	Enters privilege mode
configure terminal	Enters configuration mode
description <name-string>	Sets a description to the interface
hostname name	Sets a host name to the current Cisco network device
interface fastethernet/number	Enters interface configuration mode for the specified fast ethernet interface
default interface <interface>	Rests the specified interface to its default configuration
copy from-location to-location	copie a file (or set of files) from one location to another
copy running-config startup-config	It saves the configuration when the device reloads, it loads the latest configuration file
copy startup-config running-config	Saves the startup configuration into the running configuration
write / write memory	Save the current configuration
write erase / erase startup-config	Deletes the startup config
reload	Reboots the device
exit / end	Returns to previous mode
logout/ disable	Exit User mode
shutdown	Shuts down the interface
no shutdown	turns up the interface

Basic show Commads

Command	Purpose
show running-config	Displays the current configuration
show startup-config	Displays the configuration at startup
show interfaces	Displays detailed information about interface status
show ip protocols	Displays all the configured routing protocols
show ip interface	Displays the status for each interface
show interface status	Displays the interface line status
show mac address-table	Displays the MAC address table
show interfaces trunk	Displays trunk ports
show interfaces <interface> switchport	Disables the switchport configuration

Multilayer Switch Config Commands

Command	Purpose
ip routing	Enables layer 3 routing on a switch
no switch port	Configures the interface as a routed port

VLAN Config Commands

Command	Purpose
vlan vlan-id	Enter to Config vlan mode
show vlan/ show vlan brief	Lists each VLAN and all interfaces assigned to that VLAN but does not include trunks
switchport trunk native vlan <vlan-number>	Configures the native VLAN on a trunk port
switchport mode trunk/access	Set the interface link type as a trunk or access
show interfaces trunk	Displays information about the operational trunks along with their VLANs
encapsulation dot1q <vlan-number>	Configures the VLAN number on a router subinterface
encapsulation dot1q <vlan-id> native	Configures the native VLAN on a router subinterface
switchport trunk encapsulation dot1q	Sets the 802.1Q encapsulation on the trunk port
switchport voice vlan <vlan id>	Configures a voice VLan

DTP & VTP Config Commands

Command	Purpose
switchport mode dynamic	Configures DTP
switchport mode dynamic auto / desirable	Configures dynamic mode
switchport nonegotiate	Disables DTP negogotiation on an interface
vtp mode < client / server / tranparent>	Configure VTP mode
vtp version	Changes the VTP version
vtp domain <domain name>	Changes the VTP domain name
show vtp status	Disables VTP Config

RIP Config Commands

Command	Purpose
router rip	Enters RIP Config mode
version 2	RIP version 2
maximum-paths <number>	Modifies the number of paths RIP will perform ECMP load-balancing over
no auto-summary	Modifys the default RIPv2 behavior of automatic summarization
default-information originate	Generates a default route
show ip rip database	Displays the contents of the RIP routing database
debug ip rip	Enables RIP debugging

EIGRP Config Commands

Command	Purpose
router eigrp <Autonomous system number>	Enters EIGRP config mode
network ip-address [ wildcard-mask ]	Enables EIGRP on interfaces in the specified range
eigrp router id	Configures EIGRP router ID
no auto-summary	Modifys the default EIGRP behavior of automatic summarization
show ip eigrp neighbors	Disables EIGRP neighbors

OSPF Config Commands

Command	Purpose
router ospf number	Enters OSPF config mode
passive-interface interface	Stops sending 'Hello' messages of the specified interface
router-id number	Sets an OSPF router ID in ip format
clear ip ospf	Rests OSPF
auto-cost bandwidth megabits per second	Change the refrence bandwidth
ip ospf cost cost	Manually configure the OSPF cost
ip ospf [process-id] area [area]	Activates OSPF on an interface
ip priority [Priority]	Changes the OSPF interface priority
ip ospf process	Rests the OSPF process
ip ospf network type	Manually configure the network type
ip ospf database	Displays the contents of the OSPF routing database
bandwidth <bandwidth in kilobits>	Changes the interface bandwidth
ip ospf authentication	Enables authentication
ip ospf authentication-key <password>	Configures an OSPF password on an interface
show ip interface ospf brief	Disables each OSPF-enabled interface
show ip ospf interface interface	Displays the specified OSPF interface
show ip ospf neighbor	Disables OSPF neighbors

HSRP Config Commands

Command	Purpose
standby group number	Configures HSRP
standby version 2	HSRP version 2
standby <group number> ip IP address	Configures the virtual IP address
standby <group number> priority value	Manually configure the active router
standby <group number> preempt	Enables preemption
show standby	Displays global information for HSRP

IPv6 Config Commands

Command	Purpose
ipv6 unicat-routing	Enables IPv6 routing
ipv6 address <address/prefix> eui-64	Configures an IPv6 address
ipv6 address autoconfig
ipv6 enable	Enables IPv6
show ipv6 nterface brief
show ipv6 neighbor	Displays IPv6 neighbor table
show ipv6 route	Displays the IPv6 routing table

ACLs Config Commands

Command	Purpose
access-list <number> {deny / permit} ip wildcard mask	Configures a basic standard ACL
ip access-list standard <acl-name>	Enters standard ACL config mode
[entry number] {deny / permit} ip wildcard mask	Configures a named ACL
access-list <number> remark <remark>	Adds a remark to an ACL
ip access-group <number> {in / out}	Applys the ACL to an interface
<permit / deny> ip any any	Creates an extended ACL entry to permit or deny all traffic
show access-list	Displays all the configured ACLs
show ip access-list	Displays only IP ACLs

STP Config Commands

Command	Purpose
spanning-tree portfast	Enables portfast
spanning-tree portfast default	Enables portfast on all access ports
spanning-tree portfast bpdguard default	Enables BPDU Gurad on all portfast interfaces
spanning-tree bpdguard enable	Enbales BPDU Gurad
spanning-tree mode mode	Configures STP mode
spanning-tree vlan <vlan number> root primary	Configures the root bridge
spanning-tree vlan <vlan number> root secondary	Configures the secondary root bridge
spanning-tree vlan <vlan-id> cost <cost>	Configures the STP cost of an interface
spanning-tree vlan <vlan-id> port-priority priority	Configures the STP priority of an interface
show spanning-tree	Displays global information for STP

RSTP Config Commands

Command	Purpose
spanning-tree mode rapid-pvst	Enables rapid PVST mode
spanning-tree portfast	Configures a switchport as an RSTP edge port
spanning-tree link-type <point-to-point / shared>	Configures the RSTP switchport link type

Etherchannel Config Commands

Command	Purpose
interface port-channel <channel-group>	Enters interface config mode for the specified port channel
channel-group <interface id> mode < active / desirable / on / passive / auto >	Configures an interface to be part of an Etherchannel
channel protocol <lacp / pagp >	Manually configures the Etherchannel negotiation protocol
port channel load-balance < src-mac / dst-mac / src-dst-mac / dst-ip / src-ip / src-dst-ip >	Configures the Etherchannl load-balancing method
show etherchannel summary	Displayes the summary of the etherchannels
show etherchannle port-channel	Displays information about virtual port-channel interfaces
show etherchannel load-balance	Displays information about the load-balancing settings

CDP Config Commands

Command	Purpose
cdp run	Enables cdp
cdp enable	Enables cdp
cdp timer	Configres the CDP timer
cdp holdtime seconds	Configures cdp holdtimer
cdp advertise-v2	Configres CPDv2
show cdp	Displays global information for CDP
show cdp traffic	Displayes the cdp trafic
show cdp neighbors	Displays all CDP neighbors
show cdp entry <hostname>	Shows detailed information for a specific CDP neighbor

LLDP Config Commands

Command	Purpose
lldp run	Enables LLDP
lldp transmit	Enables LLDP transmition on a specfic interface
lldp receive	Enables LLDP to revceive
lldp timer seconds	Configures the LLDP timer
lldp holdtime seconds	Configures LLDP holdtimer
lldp reinit seconds	Configures the LLDP reinit timer
show lldp	Displays global information for LLDP
show lldp traffic	Displayes the LLDP trafic
show lldp neighbors	Displays the list of LLDP neighbors
show lldp neighbors detail	Displays more details from the list of LLDP neighbors

Clock & NTP Config Commands

Command	Purpose
clock set hh:mm:ss {day/month} {month/day} year	Manually configure the software clock
calendar set hh:mm:ss {day/month} {month/day} year	Manually configure the hardware clock
clock timezone <name of time zone> [minuits-offest]	Configures the timezone
clock update calendar	Synchronizes the hardware to the software's time
clock read calender	Synchronizes the software to the calender's time
clock summer-time reccuring <name> <start> <end> [offest]	Automatically configure summer time
ntp server <IP>	Configures ntp server
ntp master [number]	Manually configure an device to act like an ntp sever
ntp peer <IP address>	Symmetric active mode
ntp authenticate	Enable NTP authentication
ntp authentication-key <key number> md5 <key>	Create the authentication key(s)
ntp trusted-key <key-number>	Specified which key(s) is trusted
show clock	View the time
show clock detail	View the time source of the device
show calendar	View the calendar
show ntp status	View the ntp status
show ntp associations	View all the servers you configured

SNMP Config Commands

Command	Purpose
snmp-server contact contact	Configures contact infomation
snmp-server location location	Configures the location of the SNMP server
snmp-server community <string> ro	Configures the community strings (read only)
snmp-server community <string> rw	Configures the community strings (read/write)
snmp-server host <host> version 2c <string>	Configures the NMC address
snmp-server enable traps snmp linkdown linkup
snmp-server enable traps config

SYSLOG Config Commnads

Command	Purpose
logging console level	Configures logging to the console line
logging monitor level key-word	Configures logging to the VTY lines
logging buffered size level	Configures logging to the buffer
logging <server-ip>/ logging host <server-ip>	Configures logging to an external server
logging trap <level>	Limits messages that are logged to the syslog servers based on severity
logging synchronus	Prevents every logging output from immediately interrupting the console session
terminal monitor	Sends a copy of all syslog messages to Telnet or SSH
service timestamps log datetime / uptime	Enables timestamps
service squence-numbers	Enable squence numbers
show logging	Displays the device's logs

Console Port Security Commands

Command	Purpose
line console 0	Enters console configuration mode
passowrd <passowrd>	Sets up a passowrd
login	Requires a user to enter the passowrd to access the CLI
login local	login with the username
exec-timeout <minuits> <seconds>	Log out after a certain period of incativity

SSH Config Commands

Command	Purpose
crypto key generate rsa	Creates the keys that are required by SSH
ip ssh version 2	Restricts SSH version 2 only
ip domain name <name>	Configures a domain name
tranport input ssh	Limits connection to SSH only
show ip ssh	Shows if SSH is enabled or not
line vty 0 15	Access all VTY lines

FTP & TFTP Config Commands

Command	Purpose
ip ftp username <username>	Configures a username
ip ftp password <pasword>	Configures a passowrd
copy ftp: flash:	Copies files from a FTP server the device flash
copy tftp: flash:	Copies files from a TFTP server the device flash
boot system flash <file name>	Configures the new IOS
delete flash:<file name>	Deletes a file
show file systems	View the file systems on a CISCO IOS
show flash	View the contents of flash

NAT Config Commands

Command	Purpose
ip nat inside / outside	Designatea an inside or outside interface
ip nat inside source <inside local ip> <inside global ip>	Configures the one-to-one ip mappings
ip nat inside source list <acess-list> pool <pool-name>	Configures dynamic NAT by mapping to the ACL pool
ip nat inside source list <acess-listacess-list> pool <pool-name> overload	Configures PAT
ip nat inside source list <acess-list> interface <interface> overload	Configures PAT
ip nat pool <pool>	Creates a NAT pool
show ip nat translations
show ip nat statistics
clear ip nat translation *	Clears the NAT translation table

Voice vlan Commands

Command	Purpose
switchport voice vlan <vlan-id>	Configures a voice VLAN

Port security Commands

Command	Purpose
switchport port-security	Enables port security
switchport port-security mac-address <mac address>	Adds a MAC address to the list of secure MAC addresses
switchport port-security aging time <minutes / inactivity>	Configures the aging time
switchport port-security aging type <absolute / inactivity>	Configures the the aging type
switchport port-security aging static
switchport port-security violation <shutdown / restrict / protect>	Sets the action to be taken when a security violation is detected
switchport port-security maximum maximum	Sets the maximum number of secure MAC addresses on the port
switchport port-security mac-address sticky	Enables sticky secure mac address
switchport port-security mac-address sticky <mac address>	Configures a sticky mac address
errdisable recovery cause psecure-violation	Re-enables an interface
show port-security	Displays the port security interfaces
errdisable recovery interval <seconds>	Configures the timer interval
show port-security interface <interface>	Displays information about security options configured on the interface
show errdisable recovery	Displays reasons an interface is errdisabled

DHCP Snooping Commands

Command	Purpose
ip dhcp snooping	Enables DHCP snooping globally
ip dhcp snooping vlan <vlan-num>	Enables DHCP snooping on the specified VLan
ip dhcp snooping trust	Configures an interface as a trusted port
ip dhcp snooping rate limit rate <packets per second>	Configures DHCP rate limitation
errdisable recovery cause dhcp-rate-limit	Enables errdisable recovery for DHCP rate limiting
no ip dhcp snooping information option	Disables DHCP option 82
show ip dhcp snooping biding

DAI Config Commands

Command	Purpose
ip arp inspection vlan <vlan-num>	Enables DAI
ip arp inspection trust	Configures an interface as a trusted port
ip arp inspection validate <dst-mac / src-mac / ip>
ip arp inspection limit rate	Configures DAI rate limiting
errdiable recovery cause arp-inspection	Manually re-enable disabled interfaces
show ip arp inspection	Displays the summury of the DAI configuration

Client DNS Config Check Commands

Windows Commads

Command	Purpose
ipconfig /displaydns	View the DNS cache
ipconfig /flushdns	Clears the DNS cache

IOS Commands

Command	Purpose
ip dns server	Configures a router as a DNS server
ip host <host> <IP address>	Configures a list of mappings
ip name-server <IP address>	Configures an external DNS server
ip domain-name name	Configures a DNS domain name
ip domain lookup	Enables DNS lookup
show hosts	Disables the configured and learned hosts

DHCP Config Commands

Windows Commads

Command	Purpose
ipconfig /release	Releases the DHCP learned IP address
ipconfig /renew	Gets an IP address from a DHCP server

IOS Commands

Command	Purpose
ip dhcp excluded-address <low-address> <high-address>	Specifies IP addresses that a DHCP server should not assign to DHCP clients
ip dhcp pool name	Creates a DHCP pool / Entres DHCP config mode
network <network-number> <mask>	Configures the network number and mask for a DHCP address pool
default-router <address>	Specifies the default router list for a DHCP client
lease days hours minuts	Configures the lease time
lease infinit
show dhcp biding	Displays all of the DHCP clients
ip helper-address address	Configure a DHCP relay-agent
ip address dhcp	Configures a DHCP client