USEFUL COMMANDS

The order of most commands is relevant!

To “undo” a command, or to simply delete something just attach the no prefix

R(config-if)> no ipv6 address 2001:A:1:1::100/64 	# Undo's the assignment of IPv6 addr

VPC

##### VPC Commands #####
VPC> show 						    # Shows VPC Interface details
VPC> show ip						# Shows Address/MAC/Gateway/DNS ...
VPC> ip <addr> <mask> <gateway>		# Configures VPC to <addr> <mask> <gateway>

### DHCP ###
VPC> ip dhcp 						# Acquire IPv4 Address dynamically
VPC> ip dhcp -r 					# Renew the IPv4 Address Dynamically
VPC> ip dhcp -x 					# Release the IPv4 Address Dynamically

Router

##### Router Commands #####
R> show ip route 					                # Show routing table
R> show interfaces 					                # Details of each interface
R(config)> ip route <network> <mask> <gateway>		# Creates an ip route to  <network>
							# with such <mask> through <gateway>

### NAT/PAT ###
R> show ip nat translations 			 # Shows the NAT Table
R> show ip nat statistics  				 # Shows the NAT statistics

### IPv6 ###
R> show ipv6 route 
R> show ipv6 interface 					 # Detailed IPv6 configuration information for all interfaces
R> show ipv6 interface brief 		     # Summary of IPv6 interface information
R> ipv6 route <network>/<mask> <gateway> # Creates an ip route to  <network>
							# with such <mask> through <gateway>

### General Mandatory Commands ###
R(config)> service dhcp					# Enables DHCP
R(config)> ip subnet zero				# Allows the use of subnet 0
R(config)> ipv6 unicast-routing			# Enables IPv6 Routing

ESW

##### Switch Layer 3 Commands #####
SW> show run						    # Shows configuration file
SW> show ip route					    # Shows the IPv4 routing table
SW> show ipv6 route 					# Shows the IPv6 routing Table
SW> show vlan-switch					# Shows the vlan table
SW> show mac-address-table				# Shows the mac address table
SW(config)> ip route <network> <mask> <gateway>		# Creates an ip route to  <network>
							# with such <mask> through <gateway>
SW(config)> ipv6 route <network>/<mask> <gateway> 	# Creates an ip route to  <network>
							# with such <mask> through <gateway>

### Configure interface/vlan with more than 2 Addrs ###
SW> conf t
SW(config)> int <interface>
SW(config-if)> ip address <addr> <mask>
SW(config-if)> ip adddress <addr> <mask> secondary

### General Mandatory Commands ###
SW(config)> ip routing					# Allows switch to perform L3 functions
SW(config)> service dhcp				# Enables DHCP
SW(config)> ip subnet-zero 				# Allows the use of subnet zero
SW(config)> ipv6 unicast-routing 		# Enables IPv6 Routing

VLAN CONFIGURATION

Configure VLANs

ESW> vlan database					# Enter VLAN configuration mode
ESW> vlan <vlanID>					# Create <vlanID>
ESW> exit						    # Exit vlan Database

ESW(config)> ip routing				# Enable IP Routing
ESW> interface range Fx/y - z		# Selects the range of interfaces for configuration
# Choose one, either ↓ or ↑
ESW> interface Fx/y					   # Selects the interface
ESW> switchport mode access			   # Putting ports into access mode
ESW> switchport acess vlan <vlanID>	   # Assigns the selected ports to <vlanID>
ESW> end						       # Exit current configuration
ESW> write						       # Save running configuration

Set port to trunk

Configures the interface as a trunk port to carry traffic for multiple VLANs using 802.1Q encapsulation

Importante Note:

  • Ports on acess mode can only belong to one specific VLAN and the incoming and outgoing Ethernet frames DO NOT have VLAN TAG
  • Ports on trunk mode may input and output Ethernet Frames from different VLANs and those ethernet frames SHOULD BE TAGGED, as such:
ESW> interface Fx/y 					# Selects the interface
ESW> switchport mode trunk 				# Sets the selected port to trunk

Configure IP to VLAN

ESW> conf t						# Enter configuration mode
ESW> interface vlan <vlanID> 	# Select VLAN <ID> interface for configuration
ESW> ip address <addr> <mask> 	# Assigns IP addr and subnet mask to VLAN <ID>
ESW> no shutdown 				# Enables VLAN interface
ESW> end 						# Exists configuration mode
ESW> write 						# Saves configuration

Virtual Interfaces

Configure sub-interface to send and received tagged frames (encapsulation dot1Q <vlanid>)

It’s possible to add more sub-interfaces to the same physical interface (e.g F1/0.3, F1/0.450). The ID of the interface (0.3, 0.450) doesn’t need to match the <vlanID>.

R(config)> interface Fx/y				      # Selects interface Fx/y
R(config)> no shutdown       				  # Enables selected interface
R(config)> interface Fx/y.z 				  # Creates sub-interface Fx/y.z
R(config-subif)> no shutdown 				  # Enables selected interface
R(config-subif)> encapsulation dot1Q <vlanID> # Tags the sub-interface for the specified VLAN using dot1Q
R(config-subif)> ip address <addr> <mask> 	  # Assigns the addr and mask to the sub-interface
R> end 							              # Exit current configuration

NAT/PAT Configuration

Dynamic NAT/PAT

To define a pool of addresses to be allocated by dynamic NAT process:

R(config)> ip nat pool <poolName> <start-IP> <end-IP> netmask <subnet-mask>

Creates an acess list to specify which IP addresses are eligible for NAT Translation:

  • <listnum> number of the list
  • <addr> network address to be eligible for NAT Translation
  • <wildcard-mask> host bits (e.g 0.0.0.255)
R(config)> access-list <listNum> permit <addr> <wildcard-mask>

Establish the dynamic source translation, link the acess list <listNum> to the name of the NAT Pool <poolName>:

  • Add the option overload to enable PAT (NAT Overload)
R(config)> ip nat inside source list <listNum> pool <poolName> (overload)

R(config)> int fx/y					# Router Interface on the private network
R(config-if)> ip nat inside 		# Specifies interface to  be used by inside network hosts

R(config)> int fx/y					# Router Interface on the public network
R(config-if)> ip nat outsidem 		# Specifies interface to  be used by outside

R> show ip nat translations 		# Shows the NAT Table
R> show ip nat statistics  			# Shows the NAT statistics
R> clear ip nat translation *		# Clear NAT Translation Table
R> ip nat translation timeout x 	# Change NAT timeout to x seconds

Static NAT/PAT

Static translation

R(config)> ip nat inside source static <private addr> <public addr>

DHCP

To verify the configuration and status of the DHCP Server

show ip dhcp pool 					# Returns the configured DHCP Pools
show ip dhcp server statistics 		# Statics of the DHCP Server (Num of address pools; 
							        # Num of DHCP Discovers; Offer;	Request; Acknowlodge etc)
show ip dhcp binding 				# Addresses given to the different hardware

Configure the DHCP Server

R(config)> service dhcp 				          # Enables DHCP service
R(config)> ip dhcp excluded address <addr> <addr> # Interval of excluded addresses from the DHCP scope (x to y)
R(config)> ip dhcp pool <x> 				      # Creates DHCP Pool number <x>
R(dhcp-config)> network <addr> <mask>			  # Mask and Subnet Mask linked to the DHCP Pool
R(dhcp-config)> default-router <addr> 			  # Gateway

IPv6

R(config)> ipv6 unicast-routing 		# Enables IPv6 routing on the router
R(config)> interface <int> 				# Selects the interface to be configured
R(config-if)> ipv6 enable				# Enables IPv6 on the selected interface
R(config-if)> no shutdown 				# Activates the interface


### Adding Specific IPv6 Addresses ###
R(config)> interface <int> 				      # Selects the interface to be configured
R(config-if)> ipv6 address 2001:A:1:1::100/64 # Assigns IPv6 addr to selected interface
R(config-if)> no shutdown 				      # Activates the interface


### Configuring an Address using EUI-64 ###
R(config)> interface <int> 				            # Selects the interface to be configured
R(config-if)> ipv6 address 2001:A:1:2::/64 eui-64	# Configures an IPv6 Address for the interface using EUI-64
R(config-if)> no shutdown 				            # Activates the interface


### Verification Commands ###
R> show ipv6 interface 					           # Detailed IPv6 configuration information for all interfaces
R> show ipv6 interface brief 				       # Summary of IPv6 interface information