While most of us are working on routers we occasionally do an IOS upgrade while doing so we encounter some problem which will not let boot the IOS properly. I will be sharing my experience on one of my IOS upgrade in which it turn out that the flash of the router is defective in this case I end up losing the IOS i have downloaded on the flash and no way to boot up from the flash itself so I’ve check the net and found how to bypass this problem and let the router boot-up with the IOS from an TFTP itself. (This is just a workaround to make sure the router is still working while purchasing a new Flash)
Network Setup (Assuming we have the TFTP Server connected Directly to the Router)
Here’s the logs on what I’ve done.
Below you could see that it could not detect the flash which our IOS is located
System Bootstrap, Version 12.4(13r)T, RELEASE SOFTWARE (fc1) Technical Support: http://www.cisco.com/techsupport Copyright (c) 2006 by cisco Systems, Inc. Initializing memory for ECC . c2821 platform with 262144 Kbytes of main memory Main memory is configured to 64 bit mode with ECC enabled Readonly ROMMON initialized loadprog: error - on file open boot: cannot load "flash:c2800nm-advipservicesk9-mz.124-15.T9.bin" c2821 platform with 262144 Kbytes of main memory Main memory is configured to 64 bit mode with ECC enabled rommon 3 > dir flash bad device name usage: dir <device> usage: dir dir flash": monitor: missing closing " rommon 5 > dir flash: dir: cannot open device "flash:" rommon 6 > dir flash: dir: cannot open device "flash:"
Checking other media available on the router which an IOS reside so we could boot up an IOS but as you could see there are none.
rommon 7 > dev Devices in device table: id name flash: compact flash bootflash: boot flash usbflash0: usbflash0 usbflash1: usbflash1 eprom: eprom rommon 8 > dir bootflash: device does not contain a valid FS dir: cannot open device "bootflash:"
So our only option now is to boot via TFTP while on a rommon environment, to do that we need to set some parameters.
We need to set the following parameters
IP address/Subnet Default Gateway (Optional if the TFTP server is on LAN) The IOS image on the TFTP Server
Execute the tftpdnld –r
Below is the actual command in setting the parameter needed.
rommon 9 > IP_ADDRESS=10.XXX.24.2 rommon 10 > IP_SUBNET_MASK=255.255.254.0 rommon 11 > DEFAULT_GATEWAY=10.XXX.24.1 rommon 12 > TFTP_SERVER=10.XXX.24.55 rommon 13 > TFTP_FILE=c2800nm-advipservicesk9-mz.124-15.T9.bin rommon 14 > tftpdnld -r
IP_ADDRESS: 10.XXX.24.2 IP_SUBNET_MASK: 255.255.254.0 DEFAULT_GATEWAY: 10.XXX.24.1 TFTP_SERVER: 10.XXX.24.55 TFTP_FILE: c2800nm-advipservicesk9-mz.124-15.T9.bin TFTP_VERBOSE: Progress TFTP_RETRY_COUNT: 18 TFTP_TIMEOUT: 7200 TFTP_CHECKSUM: Yes TFTP_MACADDR: XXX.XXX.XXX.XXX GE_PORT: Gigabit Ethernet 0 GE_SPEED_MODE: Auto . Receiving c2800nm-advipservicesk9-mz.124-15.T9.bin from 10.XXX.24.55 !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!!!!!!!!!!!! File reception completed. Validating checksum. loading image c2800nm-advipservicesk9-mz.124-15.T9.bin program load complete, entry point: 0x8000f000, size: 0x310cb04 Self decompressing the image : ################################################## ################################################## ################################################## ################################################## ################################################## ################################# [OK] Smart Init is disabled. IOMEM set to: 20 Using iomem percentage: 20 Restricted Rights Legend Use, duplication, or disclosure by the Government is subject to restrictions as set forth in subparagraph (c) of the Commercial Computer Software - Restricted Rights clause at FAR sec. 52.227-19 and subparagraph (c) (1) (ii) of the Rights in Technical Data and Computer Software clause at DFARS sec. 252.227-7013. cisco Systems, Inc. 170 West Tasman Drive San Jose, California 95134-1706 Cisco IOS Software, 2800 Software (C2800NM-ADVIPSERVICESK9-M), Version 12.4(15)T9, RELEASE SOFTWARE (fc5) Technical Support: http://www.cisco.com/techsupport Copyright (c) 1986-2009 by Cisco Systems, Inc. Compiled Tue 28-Apr-09 13:09 by prod_rel_team Image text-base: 0x400AF910, data-base: 0x437AB3E0 Unknown file system detected. Use format command to format the card as DOS File System. Or use erase command to format the card as Low End File System. 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: http://www.cisco.com/wwl/export/crypto/tool/stqrg.html If you require further assistance please contact us by sending email to export@cisco.com. Installed image archive Cisco 2821 (revision 49.46) with 210944K/51200K bytes of memory. Processor board ID XXXXXXXXXXX 2 Gigabit Ethernet interfaces 4 Channelized (E1 or T1)/PRI ports 2 Virtual Private Network (VPN) Modules DRAM configuration is 64 bits wide with parity enabled. 239K bytes of non-volatile configuration memory. 0K bytes of ATA CompactFlash (Read/Write) % Crashinfo may not be recovered at flash:crashinfo % This file system device reports an error Press RETURN to get started!
As you could see we have successfully booted up a router via a TFTP server in a rommon environment.
Please note the that command
tftpdnld –r
direct the router to load the IOS on memory rather than downloading it to the flash which is the cause of failure.
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