How to replace cisco ios on 4221 isr router

[mohameddjelouah]

Hello i have cisco 4221 isr router and it have the sd-wan ios version and its limited for example i cant acces conf t so i downloaded a new ios 16.10 bin to replace the old one and i know how to acces rommon mode but i stopped there so if there's any guide about how to replace the old one thank you for helping am using console and i have a usb drive

[balaji.bandi · Accepted solution]

Get into ROMMON - with below steps : ( Hope you are sure what you like to do degrade or upgrade before you proceed) - ROMMON Version correct.

Copy the image to USB and turn of the device and plug in the USB, Turn on the Device and follow the process for ROMMON

Connect PC with a console cable to the router - power down the device and power and follow the break sequence.
CTRL-C does work (not some times) break the boot operation
but by sending a BREAK (for example, from putty menu, Special Command --> Break) does work,

rommon> dir usb0:  - check the image available and readable.

> boot usb0:image.bin

check the router bootable and have # prompt

copy the image from usb0: to bootflash:

(config)#no boot system bootflash:oldimag.bin
(config)#boot system bootflash:newimage.bin
#wr
#reload

copy below procedure if you like to install: you can refer below guide for reference.

https://www.cisco.com/c/en/us/td/docs/routers/access/4400/software/configuration/guide/isr4400swcfg/bm_isr_4400_sw_config_guide_chapter_0101.html