Loading IOS on Cisco switch which has no existing IOS
Home > Switch configuration notes > Loading IOS on Cisco switch which has no existing IOS
It is possible while upgrading IOS on switch that we upload some corrupted / wrong version of image. In that case switch will be left without any IOS. So telnet / http access to switch will not be available. Also even through console access we would have very limited control as there will be no way to configure switch interfaces or to contact switch from network. In such scenario the only way to upload new IOS on switch is using console connection as described below.
- Keep `mode' button pressed while switching on power to switch.
- Use command `flash_init'
- Use command `load_helper'
- Use command `copy xmodem: flash:/c2900xl-c3h2s-mz.120-5.WC17.bin' or something similar
- When switch says to begin transfer use Transfer -> Send File option in hyperterminal. Choose method for file transfer as xmodem and not zmodem.
- Note: File Transfer may take upto 45 minutes :) at speeds less than 8kbps
- Use `boot flash:/c2900xl-c3h2s-mz.120-5.WC17.bin' to boot from the newly uploaded IOS image.
- Go to `config t'
- Use command 'boot system flash:/c2900xl-c3h2s-mz.120-5.WC17.bin'
- Use `show boot' to verify boot configuration.
- Try reload
Disabling boot helper
If switch is not booting with manually loaded image even after changing boot path with
boot system flash:/<file_path>
then use
no boot boothlpr
to erase from env_vars file values like BOOTHLPR path-list: buffersize after command the env_vars would have line like HELPER path-list:
Home > Switch configuration notes > Loading IOS on Cisco switch which has no existing IOS
