Switch configuration is crucial for optimizing network performance, enhancing security, and enabling efficient traffic management. It helps prevent unauthorized access, reduces network congestion through VLANs, and ensures redundancy with protocols like STP. Mastering switch configuration is essential for troubleshooting, securing, and maintaining a reliable IT infrastructure.
- Basic VLANs access points commands and verification
- Learned how to configure switches through CLI command to get to configuration mode
- Learned how to assign different VLANs and Ports to the switch through CLI command
- Learned how to use command prompt on the PC to ping the other ones to see if they can communicate. This is especially important if you have two or more computers on a switch that belongs to two different departments.
- Learned other switch verification commands to use
- CISCO Packet Tracer
Ref 1: Example of a simple network example where a switch is connected to two computers with two simple static IP addresses as labeled on the image
Ref 2: Using the command prompt on the first computer (PC0) to ping the second computer (PC1) to see if they're connected and they are because they're connected to the same switch
Ref 3: Setting up some basic switch configuration, VLAN. For example we label PC0 as "User" and PC1 as "Accounting". We do not want them to communicate to each other.
Ref 4: We can put the User (PC0) on VLAN 2 and Accounting (PC1) on VLAN 3 so that they're on two different logical network
Ref 5: Configuring the switch by going to the CLI prompt and entering "enable" to enable privilaged exec mode "Switch#"
Ref 6: From "Switch#" enter command config t (configure terminal) to get "Switch(config)#, which is the configuration mode
Ref 7: Before we configure a switch we want to make sure there's no pre-existing VLAN on it. To do that type in "exit" from the terminal (Switch(config)#exit), then "Switch#show vlan" to see if there's any pre-existing VLAN
Ref 8: Configuring VLAN on the switches by using the command "Switch(config-vlan)#name User-VLAN2", then exit out of that command and do it again for the second computer. Same command "Switch(config-vlan)# name Accounting-VLAN3"
Ref 9: To verify if the VLANs were configured correctly use command "Switch(config-vlan)#do show vlan" and there should be two additional VLANs including the default. "do" forces the command in CLI.
*Ref 10: To assign a port to VLAN2, hover over the green arrow by the switch to find the port, which is Fa0/1 in this example. So from there enter the command "Switch(config)#int Fa0/1
Ref 11: Configuring this port "Fa0/1" into an access port
Ref 12: Applying Fa/0/1 to access port vlan 2. As you can see the orange circle means that the switch is resetting to the new configuration
Ref 13: Now we do the same for the Accounting computer and assign it vlan3
Ref 14: Type in command "Switch(config-if)#do sh vlan" to see if the port configurations were done correctly and they are
Ref 15: Go back to (PC0) > command prompt > ping 192.168.1.2 to see if they can communicate with each other but they can't because they're both on two different VLAN, which is what we want
Ref 16: Connecting another computer to the switch and repeating the similar processes as before
Ref 17: Once the process is complete Accounting-VLAN should have two ports assigned to it
TIP 1: If you don't remember the next command prompt then press "?" and it'll provide you a list
TIP 2: Always remember to save your configurations incase the switch turns off. Use the command "exit" to go back to "Switch#" and from there type in "Switch#copy running-config startup-config, press enter two times to confirm. If you see [OK] it means your configuration was saved correctly - Though this is what the exam wants, in the real world use the short cut "Switch#wr" and it'll do the same thing.
TIP 3: Other command prompts to use to verify configuration on the switch. Use "Switch#int fa0/1 switchport" to give you the information about it to see if its enabled or disabled, what kind of ports it has, and see what vlan its on
*TIP 4: To show only information on a specific vlan. i.e "Switch#sh vlan id 2"
