Cisco Commands
Comprehensive Cisco IOS commands reference from legacy to modern versions.
Basic Navigation
enableEnter privileged EXEC mode
disableExit privileged EXEC mode
configure terminalEnter global configuration mode
exitExit current mode
endExit to privileged EXEC mode from any config mode
show running-configDisplay current running configuration
show startup-configDisplay startup configuration
reloadReboot the device
copy running-config startup-configSave running config to startup config
write memorySave configuration (legacy command)
Interface Configuration
interface <type> <number>Enter interface configuration mode
ip address <IP> <subnet-mask>Configure IP address on interface
no shutdownEnable interface
shutdownDisable interface
description <text>Add interface description
speed <10|100|1000|auto>Set interface speed
duplex <auto|full|half>Set duplex mode
switchport mode <access|trunk>Configure switchport mode
switchport access vlan <vlan-id>Assign VLAN to access port
switchport trunk allowed vlan <vlan-list>Set allowed VLANs on trunk
channel-group <number> mode <on|auto|desirable|active|passive>Configure EtherChannel
VLAN Configuration
vlan <vlan-id>Create VLAN and enter VLAN config mode
name <vlan-name>Name the VLAN
show vlan briefDisplay VLAN summary
show vlan id <vlan-id>Display specific VLAN information
no vlan <vlan-id>Delete a VLAN
switchport trunk native vlan <vlan-id>Set native VLAN for trunk
vtp mode <server|client|transparent>Set VTP mode
vtp domain <domain-name>Set VTP domain
vtp password <password>Set VTP password
Routing - Static
ip route <network> <mask> <next-hop|interface>Configure static route
ip route 0.0.0.0 0.0.0.0 <next-hop>Configure default route
show ip routeDisplay routing table
show ip route staticDisplay only static routes
no ip route <network> <mask> <next-hop>Remove static route
ip route <network> <mask> <next-hop> <distance>Static route with admin distance
Routing - OSPF
router ospf <process-id>Enable OSPF routing
network <network> <wildcard> area <area-id>Advertise network in OSPF
router-id <router-id>Set OSPF router ID
passive-interface <interface>Set interface as passive
default-information originateAdvertise default route
show ip ospf neighborDisplay OSPF neighbors
show ip ospf interfaceDisplay OSPF interface information
show ip ospf databaseDisplay OSPF topology database
clear ip ospf processReset OSPF process
ip ospf cost <cost>Set OSPF cost on interface
ip ospf priority <priority>Set OSPF priority for DR election
Routing - EIGRP
router eigrp <as-number>Enable EIGRP routing
network <network>Advertise network in EIGRP
no auto-summaryDisable automatic summarization
passive-interface <interface>Set interface as passive
show ip eigrp neighborsDisplay EIGRP neighbors
show ip eigrp topologyDisplay EIGRP topology table
show ip eigrp interfacesDisplay EIGRP interfaces
metric weights <tos> <k1> <k2> <k3> <k4> <k5>Configure EIGRP metric
variance <multiplier>Configure EIGRP load balancing
Security - Access Lists
access-list <number> <permit|deny> <source> <wildcard>Create standard ACL (1-99)
access-list <number> <permit|deny> <protocol> <source> <dest>Create extended ACL (100-199)
ip access-list standard <name>Create named standard ACL
ip access-list extended <name>Create named extended ACL
ip access-group <acl> <in|out>Apply ACL to interface
show access-listsDisplay all ACLs
show ip access-lists <name|number>Display specific ACL
no access-list <number>Remove ACL
access-list <number> remark <text>Add comment to ACL
Security - Port Security
switchport port-securityEnable port security
switchport port-security maximum <count>Set max MAC addresses
switchport port-security mac-address <mac>Configure static secure MAC
switchport port-security mac-address stickyEnable sticky MAC learning
switchport port-security violation <shutdown|restrict|protect>Set violation mode
show port-securityDisplay port security status
show port-security addressDisplay secure MAC addresses
show port-security interface <interface>Display interface port security
clear port-security sticky interface <interface>Clear sticky MAC addresses
Spanning Tree Protocol
spanning-tree mode <pvst|rapid-pvst|mst>Set STP mode
spanning-tree vlan <vlan-id> root primarySet bridge as root
spanning-tree vlan <vlan-id> root secondarySet bridge as secondary root
spanning-tree vlan <vlan-id> priority <priority>Set STP priority
spanning-tree portfastEnable PortFast on interface
spanning-tree bpduguard enableEnable BPDU Guard
show spanning-treeDisplay STP information
show spanning-tree summaryDisplay STP summary
spanning-tree guard rootEnable Root Guard
ISE Integration
aaa new-modelEnable AAA
address ipv4 <ip> auth-port <port> acct-port <port>Set RADIUS server address
key <key>Set RADIUS shared secret
aaa group server radius <group-name>Create RADIUS server group
server name <server-name>Add server to group
aaa authentication dot1x default group <group>Configure 802.1X authentication
dot1x system-auth-controlEnable 802.1X globally
authentication port-control autoEnable 802.1X on interface
show dot1x allDisplay 802.1X status
Device Management
hostname <name>Set device hostname
enable secret <password>Set encrypted enable password
service password-encryptionEncrypt all plaintext passwords
banner motd # <message> #Set MOTD banner
line console 0Enter console line configuration
line vty 0 4Enter VTY line configuration
password <password>Set line password
loginRequire login on line
logging synchronousPrevent log messages from interrupting input
exec-timeout <minutes> <seconds>Set inactivity timeout
Diagnostics & Troubleshooting
show versionDisplay system version and hardware info
show interfacesDisplay all interface status
show interfaces statusDisplay interface line status
show ip interface briefDisplay brief IP interface status
show mac address-tableDisplay MAC address table
show arpDisplay ARP table
show cdp neighborsDisplay CDP neighbors
show cdp neighbors detailDisplay detailed CDP neighbor info
show processes cpuDisplay CPU utilization
show memoryDisplay memory statistics
show logDisplay system log messages
debug <protocol>Enable debugging for protocol
undebug allDisable all debugging
terminal monitorSend log messages to current session
High Availability
standby <group> ip <virtual-ip>Configure HSRP virtual IP
standby <group> priority <priority>Set HSRP priority
standby <group> preemptEnable HSRP preemption
show standbyDisplay HSRP status