Efficiently using PuTTY to capture switch configuration details

In network administration, gathering configuration details from switches is a routine but critical task. Whether you’re auditing a device, troubleshooting an issue, or preparing for a migration, having a complete snapshot of the switch’s current state is essential. One of the most efficient ways to capture switch configuration details is by using PuTTY, a lightweight and reliable SSH/Telnet client. 

This blog outlines a streamlined approach to using PuTTY for capturing switch configuration details. By following these steps, you can ensure that your session is logged properly and that all relevant commands are executed in a single pass. 

Step 1 – Launch PuTTY and Enter the Switch IP Address 

Start by opening PuTTY. In the Session category, enter the IP address of the switch you want to connect to in the Host Name (or IP address) field. Ensure the connection type is set to SSH (or Telnet, depending on your switch configuration). 

This establishes the basic connection parameters. 

Step 2 – Enable Session Logging 

Before initiating the connection, configure PuTTY to log your session output. This is crucial for capturing the switch’s responses to your commands. 

1. In the left-hand tree menu, expand the Session category. 
2. Click on Logging. 
3. Change the Session logging option from None to Printable output. 
4. Specify a log file name and location. I prefer using the format SwitchName.&M.&D.&Y.txt.  

Using the variables &M, &D and &Y automatically enter the correct date on the filename. This setting ensures that all readable output from the switch is saved to a file, which can be reviewed or archived later. 

Step 3 – Open the Connection and Sign In 

Click Open to initiate the session. A terminal window will appear. Log in using your credentials. 

Tip: Maximize the PuTTY window before proceeding. This helps avoid line wrapping issues and ensures that the output is captured cleanly in the log file. 

Step 4 – Paste the Command Set 

To efficiently gather all relevant configuration and status information, prepare a set of commands in your clipboard. Once logged in, simply right-click inside the PuTTY window to paste the entire set. 

Here’s a recommended command list: 

terminal length 0 
more system:running-config 
show ver 
show hardware 
show license summary 
show license all 
show switch 
show etherchannel summary 
show etherchannel detail 
show clock 
show access-lists 
show vlan 
show vlan brief 
show vtp status 
show cdp neighbors 
show cdp neighbors detail 
show int trunk 
show inventory 
show ip int brief 
show ip route 
show mac address-table 
show tech-support 

Let’s break down why these commands are useful: 

• terminal length 0: Prevents paginated output, ensuring full command results are displayed without interruption. 
• more system:running-config: Displays the active configuration. 
• show ver, show hardware, show inventory: Provide hardware and software version details. 
• show license summary, show license all: Reveal licensing status. 
• show switch, show etherchannel summary/detail: Show switch stack and link aggregation details. 
• show clock: Confirms system time. 
• show access-lists, show vlan, show vlan brief: Display security and VLAN configurations. 
• show vtp status: Indicates VTP mode and domain. 
• show cdp neighbors/detail: Lists connected Cisco devices. 
• show int trunk, show ip int brief, show ip route: Provide interface and routing information. 
• show mac address-table: Displays MAC address mappings. 
• show tech-support: A comprehensive diagnostic output useful for deeper troubleshooting. 

Step 5 – Monitor and Confirm Completion 

Once the commands are pasted, PuTTY will execute them sequentially. You can monitor the output in real time. When the switch returns to the command prompt and is ready for new input, the session has completed. 

At this point, your log file contains all the output from the commands. You can close the session or continue working interactively. 

Best Practices and Considerations 

• Use consistent naming for log files: Include the switch name and date for easy reference. 
• Review logs for anomalies: Look for unexpected configurations or errors. 
• Secure your logs: Configuration files may contain sensitive information. Store them securely and restrict access. 

Conclusion 

Using PuTTY to capture switch configuration details is a simple yet powerful method for network documentation and troubleshooting. By enabling logging and executing a comprehensive command set, you can gather all necessary information in one efficient session. 

This approach minimizes manual effort, reduces the chance of missing critical data, and provides a reliable record for future reference. Whether you’re preparing for a network upgrade or conducting routine audits, this method ensures you have the insights needed to make informed decisions. 

Have any questions about using PuTTY for switch configuration details? Please reach out to our team of experts at any time!