How to Enable SSH in Cisco Switch
In today’s digital age, network security is of paramount importance. One of the essential security measures for securing network devices is enabling SSH (Secure Shell) on Cisco switches. SSH provides a secure way to access and manage your switch, ensuring that sensitive information is protected from unauthorized access. This article will guide you through the steps to enable SSH in a Cisco switch.
Step 1: Access the Cisco Switch
Before enabling SSH, you need to access the Cisco switch. You can do this by connecting a console cable to the switch’s console port and using a terminal emulator program, such as PuTTY, to establish a serial connection. Once connected, you will be prompted to log in with the switch’s username and password.
Step 2: Enter Configuration Mode
After logging in, you need to enter configuration mode. This can be done by typing the following command:
“`
enable
“`
You will be prompted to enter the enable password. Enter the password and press Enter. Once you are in enable mode, type the following command to enter global configuration mode:
“`
configure terminal
“`
Step 3: Configure SSH Settings
In global configuration mode, you need to configure the SSH settings. The following commands will enable SSH on your Cisco switch:
“`
ip ssh version 2
“`
This command enables SSH version 2, which is more secure than version 1.
“`
username [username] secret [password]
“`
Replace [username] with the desired username and [password] with the desired password. This command creates a new user with the specified username and password.
“`
ip ssh authentication-retries 3
“`
This command sets the maximum number of authentication attempts to 3. If the user fails to authenticate within these attempts, the SSH session will be terminated.
“`
ip ssh time-out 15
“`
This command sets the SSH session timeout to 15 minutes. If there is no activity for 15 minutes, the session will automatically close.
Step 4: Configure SSH Access Control List (ACL)
To further secure your SSH connection, you can configure an access control list (ACL) that specifies which IP addresses are allowed to connect to the switch via SSH. To do this, enter the following commands:
“`
access-list [number] permit tcp [source_ip] 0.0.0.0 22
“`
Replace [number] with the desired ACL number, [source_ip] with the IP address or range of IP addresses allowed to connect to the switch via SSH. The destination port is 22, which is the default port for SSH.
“`
ip ssh authorization [number]
“`
This command assigns the ACL to the SSH service.
Step 5: Save the Configuration
After configuring SSH and the access control list, you need to save the configuration to ensure that the changes persist after a reboot. To save the configuration, type the following command:
“`
write memory
“`
Step 6: Test SSH Connection
Finally, you can test the SSH connection to ensure that everything is working correctly. Use a terminal emulator program to connect to the switch’s IP address and port 22. Enter the username and password when prompted.
Congratulations! You have successfully enabled SSH on your Cisco switch. By following these steps, you have taken an essential step towards securing your network device and protecting sensitive information.
