How to Delete Startup Config in Cisco Devices
Deleting the startup configuration on a Cisco
router or switch is a common task for network engineers, especially when troubleshooting
or preparing devices for lab environments. If you want to reset your Cisco
device back to factory defaults, you can do it easily from the Cisco CLI.
In this guide, you’ll learn what startup config
is, why it matters, and the exact commands to erase it safely.
🔍 What Is the Startup Config?
Cisco devices store two types of configuration:
- Running-config – the active configuration currently used
by the device
- Startup-config – the saved configuration stored in NVRAM
that loads when the device boots
Removing the startup-config resets the device to
its default settings.
🧰
Step-by-Step: How to Delete Startup Config
1. Enter Privileged
EXEC Mode
Open your terminal and run:
enable
2. Erase the
Startup Config
Use either of the following commands:
write erase
or
erase startup-config
Both commands clear the configuration stored in
NVRAM.
3. Reload the
Device
Restart the device to complete the reset:
reload
When prompted:
Proceed with reload? [confirm]
After reboot, your router or switch will load
with no configuration and show the initial setup dialog, confirming the
reset.
⚠️ Important Notes
- This clears only the startup-config,
not the running-config.
- You must reload after erasing to
complete the reset.
- Perfect for labs, testing, or cleaning used
devices.
❓ Frequently Asked Questions (FAQ)
1. What does
deleting the startup-config do in Cisco?
Deleting the startup-config removes the saved
configuration stored in NVRAM. After a reboot, the device loads with no
configuration, similar to a factory reset.
2. Will deleting
the startup-config affect the running-config?
No. The running-config stays active until you
reload the device. The reset only takes effect after the reboot.
3. What command
deletes the startup-config in Cisco?
You can use:
write erase
or
erase startup-config
Both commands erase the saved configuration.
4. How do I fully
reset my Cisco router or switch to factory defaults?
1.
Enter privileged
EXEC mode
2.
Run write erase or erase
startup-config
3.
Reload the device
After reboot, the device will start fresh without configuration.
5. Why is my Cisco
device still showing old settings after erase?
It means you erased the startup-config but did
not reload. You must reboot for the changes to take effect.
6. Can I delete the
running-config too?
Yes, but it will immediately remove all active
configuration. You can use:
erase running-config
or manually reload without saving:
reload
When asked to save configuration, choose no.
7. Is deleting
startup-config safe?
Yes, as long as you know the device will reboot
with no configuration. It's commonly used in labs, testing, and before
reselling equipment.
0Comments