#HOW TO RECOVER CISCO ROUTER FROM ROMMON MODE UPGRADE#

Since you have already determined that the cause of the router booting up in ROMmon is not due to the configuration register value, the only option available for recovery is to re-install or upgrade the Cisco IOS software from a TFTP server using the built-in boot image (Rx-boot) in ROM.

#HOW TO RECOVER CISCO ROUTER FROM ROMMON MODE INSTALL#

There is only one way to install an image on the 2500, 3000, AS5100, or uBR900 Series Routers if the main Cisco IOS software has been deleted or corrupted. Download Cisco IOS Image Using the Boot Image from a Trivial File Transfer Protocol (TFTP) Server If the router boots up in ROMmon again, proceed to Download Cisco IOS Image Using the Boot Image from a Trivial File Transfer Protocol (TFTP) Server. If the router boots up successfully, then the cause was a configuration register value issue. UBR924 platform with 16384 Kbytes of main memory. System Bootstrap, Version 12.0(6r)T3, RELEASE SOFTWARE (fc1)Д¬opyright (c) 1999 by cisco Systems, Inc.

You must reset or power cycle the router for the new configuration to take effect: rommon 2> reset If the ROMmon prompt is 'rommon #>', type the following at the prompt: rommon 1> confreg 0x2102 System Bootstrap, Version 11.0(10c)XB2, RELEASE SOFTWAREДў500 processor with 16384 Kbytes of main memory If the ROMmon prompt is '>', type the following at the ROMmon prompt: > o/r 0x2102 The procedure for this is explained below. If the router has a valid Cisco IOS software image, then simply changing the configuration value register to 0x2102 will recover the router. Determine whether the cause is due to the change of the configuration register value, or a corrupted Cisco IOS software image. The first thing that needs to be investigated is why the router is booting up in ROMmon mode (indicated by the 'rommon # >' or '>' prompt). ConventionsДЇor more information on document conventions, see the Cisco Technical Tips Conventions. If you are working in a live network, ensure that you understand the potential impact of any command before using it. All of the devices used in this document started with a cleared (default) configuration. The information presented in this document was created from devices in a specific lab environment. The information in this document is based on the:Д¬isco AS5100 Series Universal Access Server

#HOW TO RECOVER CISCO ROUTER FROM ROMMON MODE HOW TO#

You must know how to copy the Cisco IOSВ® software image from a TFTP server to the router. Recovering a router from ROMmon is not possible by telneting to any of the interfaces.

To recover a router from ROMmon mode, the router should be physically accessible and should have a terminal connected to the console port. This document explains how to recover Cisco 2500, 3000, AS5100, and uBR900 Series Routers stuck in ROMmon ( rommon#> or > prompt).

How to recover cisco router from rommon mode