Imagine spending hours configuring VLANs, ACLs, and OSPF on a Cisco switch (exactly what we've done together in earlier tutorials in this section), and then that device suffers a hardware failure or gets accidentally reset. Without a backup, you'd have to type everything from scratch again. This tutorial eliminates exactly that risk.
Two types of configuration files in Cisco IOS
First, you need to understand the difference between these two:
running-config: the settings the device is currently operating with (in RAM, lost on device restart).
startup-config: the settings the device loads when it powers on (stored in non-volatile NVRAM).
Every change we've made throughout this series only applied to running-config — until you save it to startup-config, it's lost on a restart.
Step 1: Save the current settings to the device's permanent memory
Before any external backup, make sure it's at least saved on the device itself:
enable
copy running-config startup-config
Step 2: Set up a TFTP server on your own computer
TFTP (Trivial File Transfer Protocol) is the simplest and most common way to transfer configuration files between Cisco equipment and a computer. Install and run a free TFTP server program (like Tftpd64 on Windows) on a computer connected to the same network — this program designates a specific folder as the file storage location.
Step 3: Backing up from the switch to your computer
From the switch's command line:
enable
copy running-config tftp
The system asks for the TFTP server's IP address (your computer) and a destination filename — for example:
Address: 192.168.1.50
Destination filename: sw1-backup.cfg
Within a few seconds, the complete configuration file is saved on your computer — a plain text file you can open and read in any text editor.
Step 4: Restoring settings from a backup file
Say the switch got reset and you want to bring back the previous configuration:
enable
copy tftp running-config
Enter the TFTP server address and filename (sw1-backup.cfg) again. The system reads the file's content and applies it command-by-command to running-config — exactly as if you'd typed it all in again yourself, but in seconds.
For this to survive a restart too, don't forget:
copy running-config startup-config
Step 5: An alternative without TFTP — copying text directly
If TFTP isn't available, the simplest manual method is:
show running-config
Copy the full output and save it to a text file. To restore, enter Global Configuration mode (configure terminal) and paste the entire saved text — slower and more error-prone than TFTP, but works when no other tool is available.
Pro tip: automated, periodic backups
In real enterprise networks, this process is usually run automatically and daily/weekly across all switches and routers via a script or network management tool — not just done manually once.
Why is this skill critical?
Hardware failure, power loss at the wrong moment, or even a typo with the write erase command that wipes everything — all of these are real and common. Having a fresh backup on hand is the difference between a few minutes of delay and hours (or days) of rebuilding from scratch — exactly the operational discipline emphasized in my CCNA and network management courses.
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