Cicso C9800-L-C boot on Rommon mode

[fyf002lb]

needed to factory reset my WLC suddenly an electricity cut out while resetting when the WLC reboot it appear that there's no OS and no flash any advice on how to proceed the OS installation i already downloaded the OS that need from the cisco software and put it on a USB drive since  don't have a ftp server so is there any instruction how to proceed the OS C9800-L-universalk9_wlc.17.09.04a.SPA.bin contain the image of the flash and everything needed to run it.
thank you 

[Leo Laohoo · Accepted solution]

Well, if the WLC is in ROMMON, FTP/TFTP is not going to help because direct physical access (via console cable) is your only avenue.  

Plug the USB flash drive into the WLC and use the command "boot usbflash0:filename.bin".  

NOTE:  For "consistency" purposes, if the syntax "usbflash0:" is not accepted, try "usb0:".

[jagan.chowdam · Accepted solution]

Refer "Load image through USB" section from the following link

https://www.cisco.com/c/en/us/support/docs/wireless/catalyst-9800-series-wireless-controllers/214012-recovering-a-catalyst-9800-controller-fr.html

Jagan Chowdam