How and Why to Reset Your Cisco 9300 Switch: A Practical Guide with Real-World Tips

Resetting a Cisco Catalyst 9300 switch may seem straightforward, but it’s a critical skill that network admins often need when deploying new devices, repurposing hardware, or recovering from configuration issues. In this guide, I’ll walk you through not just the steps but also some real-world insights that can save you time and headaches.

Why Would You Reset a Cisco 9300?

Imagine inheriting a switch with unknown or forgotten passwords or trying to fix a network glitch caused by a misconfiguration. Resetting the switch to factory defaults gives you a clean slate to start fresh.

But be warned: resetting is not just about clearing settings. It can impact licensing, VLAN setups, and possibly your entire network topology if not done with proper preparation.

A Real-World Story: Recovering From a Locked-Out Switch

Recently, a client called in panic: they’d forgotten the admin password on their Cisco 9300, and critical operations were at risk. We used the ROMMON mode recovery to regain access without losing physical hardware or waiting for replacements.

Here’s how that worked and what you can learn from it.

Step-by-Step: Resetting Your Cisco 9300 Switch

Step 1: Connect to the Console

Use an RJ-45 or USB console cable to connect your PC. Open terminal software such as PuTTY or SecureCRT, and set the serial parameters:

• 9600 baud rate

• 8 data bits

• No parity

• 1 stop bit

• No flow control

Step 2: Factory Reset Using CLI (Fast and Effective)

If you have access, this method wipes the startup configuration:

Switch> enable
Switch# write erase
Switch# reload

When asked to save changes before reload, type no to ensure a clean reset.

Step 3: Password Recovery via ROMMON Mode

If locked out, do this:

1. Power cycle the switch.

2. Press and hold the Mode button until you see the switch:prompt.

3. Enter:

switch: SWITCH_IGNORE_STARTUP_CFG=1
switch: boot

4. At the prompt:

Switch> enable
Switch# write erase
Switch# configure terminal
Switch(config)# no system ignore startupconfig switch all
Switch(config)# end
Switch# reload

This boots the switch, ignoring the old config, then erases it permanently.

Step 4: Loading a New Configuration

After reset, you can load a new config from USB or TFTP:

• From USB:

Switch# copy usbflash0:new-config.txt running-config

• From TFTP:

Switch# copy tftp://<server-ip>/new-config.txt running-config

Step 5: Save Your New Configuration

To make the new settings permanent:

Switch# copy running-config startup-config

Or simply:

Switch# write memory

Common Pitfalls and Tips

• Always back up your current config before resetting.

• Be aware that after a reset, Cisco switches enter Smart Licensing evaluation mode; make sure you register and activate licenses to avoid service interruptions.

• Avoid interrupting the reload process—power loss during reboot can cause corruption.

• If working across VLANs or stacks, verify all devices support your config changes.

Final Thoughts

Resetting your Cisco 9300 doesn’t have to be stressful. With the right tools and understanding, you can quickly regain control and deploy fresh configurations safely. Keep backups readily available, familiarize yourself with your licensing requirements, and practice these steps in a lab environment before implementing critical production changes.