How to Configure a Cisco Switch?

Generally speaking, the Cisco switches are the best in the market. Versatile, reliable, flexible and powerful, the Cisco switch product line (such as the 2960, Cisco 3560, Cisco 3750, 4500, 6500, etc.) offer unparalleled performance and features.

Although a Cisco switch is a much simpler network device compared with other devices (e.g. routers and firewalls), many people have difficulties in configuring a Cisco Catalyst Switch. Unlike other lower class switch vendors (which are plug-and-play), the Cisco switch needs some initial basic configuration in order to enable management, security and some other important features.

How to configure a Cisco switch from scratch? Basic steps help you finish the Cisco switch configuration.

STEP1: Connect to the device via console

Use a terminal emulation software such as PuTTY and connect to the console of the switch. You will get the initial command prompt “Switch>”

Type “enable” and hit enter. You will get into privileged mode (“Switch#”) 

Now, get into Global Configuration Mode:

Switch# configure terminal
Switch(config)#

STEP2: Set up a hostname for the particular switch to distinguish it in the network

Switch(config)# hostname access-switch1
access-switch1(config)#

STEP3: Configure an administration password (enable secret password)

access-switch1(config)# enable secret somestrongpass

STEP4: Configure a password for Telnet access

access-switch1(config)# line vty 0 15
access-switch1(config-line)# password strongtelnetpass
access-switch1(config-line)# login
access-switch1(config-line)# exit
access-switch1(config)#

STEP5: Define which IP addresses are allowed to access the switch via Telnet

access-switch1(config)# ip access-list standard TELNET-ACCESS
access-switch1(config-std-nacl)# permit 10.1.1.100
access-switch1(config-std-nacl)# permit 10.1.1.101
access-switch1(config-std-nacl)# exit

!Apply the access list to Telnet VTY Lines
access-switch1(config)# line vty 0 15
access-switch1(config-line)# access-class TELNET-ACCESS in
access-switch1(config-line)# exit
access-switch1(config)#

STEP6: Assign IP address to the switch for management

!Management IP is assigned to Vlan 1 by default
access-switch1(config)# interface vlan 1
access-switch1(config-if)# ip address 10.1.1.200 255.255.255.0
access-switch1(config-if)# exit
access-switch1(config)#

STEP7: Assign default gateway to the switch

access-switch1(config)# ip default-gateway 10.1.1.254

STEP8: Disable unneeded ports on the switch

! This step is optional but enhances security
! Assume that we have a 48-port switch and we don’t need ports 25 to 48

access-switch1(config)# interface range fe 0/25-48
access-switch1(config-if-range)# shutdown
access-switch1(config-if-range)# exit
access-switch1(config)#

STEP9: Save the configuration

access-switch1(config)# wr

The above are some steps that can be followed for basic set-up of Cisco switches. Of course there are more things you can configure (such as SNMP servers, NTP, AAA etc) but those depend on the requirements of each particular network.