Showing results for 
Search instead for 
Did you mean: 

Switch configuration erased automatically



Last day my Cisco 4507 switch configuration got erased completely. Even startup configuration was blank.  The show version output is shown below.

JEDFOBCF0SW01#sh ver
Cisco IOS Software, Catalyst 4500 L3 Switch Software (cat4500-ENTSERVICESK9-M),
Version 12.2(40)SG, RELEASE SOFTWARE (fc2)
Technical Support:
Copyright (c) 1986-2007 by Cisco Systems, Inc.
Compiled Wed 07-Nov-07 18:00 by prod_rel_team
Image text-base: 0x10000000, data-base: 0x11ADF0B8

ROM: 12.2(31r)SGA1
Dagobah Revision 226, Swamp Revision 32

JEDFOBCF0SW01 uptime is 2 weeks, 2 days, 13 hours, 32 minutes
Uptime for this control processor is 2 weeks, 2 days, 13 hours, 32 minutes
System returned to ROM by power-on
System image file is "bootflash:cat4500-entservicesk9-mz.122-40.SG.bin"

This product contains cryptographic features and is subject to United
States and local country laws governing import, export, transfer and
use. Delivery of Cisco cryptographic products does not imply
third-party authority to import, export, distribute or use encryption.
Importers, exporters, distributors and users are responsible for
compliance with U.S. and local country laws. By using this product you
agree to comply with applicable laws and regulations. If you are unable
to comply with U.S. and local laws, return this product immediately.

A summary of U.S. laws governing Cisco cryptographic products may be found at:

If you require further assistance please contact us by sending email to

cisco WS-C4507R-E (MPC8245) processor (revision 14) with 524288K bytes of memory
Processor board ID FOX1217G8TA
MPC8245 CPU at 333Mhz, Supervisor IV
Last reset from PowerUp
18 Virtual Ethernet interfaces
22 Gigabit Ethernet interfaces
403K bytes of non-volatile configuration memory.

Configuration register is 0x2101


Kindly help on identifying the problem.

7 Replies 7

Leo Laohoo
Hall of Fame
Hall of Fame

Why is your blade's Configuration Register set to 0x2101?

Use of the Configuration Register on All Cisco Routers

This config register value will not erase the configurtion right?

Kindly correct me ?

Correct, it would not.

Did you lose power to the switch recently? Does anybody else have access to the switch and could they have erased it?

Thanks a lot for your reply. There was a lose of power just before the problem. Also since the switch is connected to raw power, this happens often. Kindly tell me whether this will create a problem. This is first time i faces this problem. No one has access of this switch other than me and hence no one could have erased.

Kindly share me any doc or bug id which can cause configuration erase because of power problem


Kindly share the reason , if any one knows, why switch configuration is getting erased after power cycle

Post entire config please.

Tharak Abraham


Did you or any other Engrs introduce a new Cisco switch in the domain somewhere ?

I mean this is a really basic thing that ppl come across when introducing a new switch in the domain without checking the config revision no.

Pls ignore if this is not the case or if you did a downgrage of IOS on the other hand.


Getting Started

Find answers to your questions by entering keywords or phrases in the Search bar above. New here? Use these resources to familiarize yourself with the community: