AP 9115 IOS update error

[heyjunsun]

hello 

ERROR occurred during AP 9115 IOS upgrade.

Initially, the situation shifted from the WLC CLI to the CAPWAP CLI, via the "wireless ewc-app shell."

In CAPWAP mode "archive download-sw /reload tftp://172.19.96.10/ap1g7-k9w8-tar.153-3.JPR.tar

At first, it was like IOS was being upgraded

After typing, it appears as an unknown character when booting up, as in the picture, and the command does not work.

[Mark Elsen]

           - Does your terminal equipment (still) use correct baud rate for accessing the AP ?

 M.

[heyjunsun]

yes 9600 baud rate use 

It worked well before IOS upgrade.

[Leo Laohoo]

Restart the putty terminal.

[heyjunsun]

I've rebooted the terminal several times and the AP has rebooted several times. Any other expected issues?

[Leo Laohoo]

Use a different computer.

[balaji.bandi]

When you started upgrade is the putty outcome ok ?

try some different baud rates :

https://www.cisco.com/c/en/us/support/docs/storage-networking/management/217970-troubleshoot-and-apply-correct-terminal.html

[heyjunsun]

Yes, it's the correct baud rate 9600.
It worked well even before IOS upgrade. Doesn't upgrading IOS change the baud rate?

Doesn't the baud rate not change even if the IOS changes?

[Mark Elsen]

                 >...Doesn't the baud rate not change even if the IOS changes?
 - It shouldn't  ; try tapping the space bar when the weird characters appear , (check if that can help)

 M.

[Rich R]

It should not change but it has been known to happen - so as others have said try other rates.
Or try a different console cable - generally those with genuine FTDI chipset are most reliable,

[heyjunsun]

hello 

Like you said, I tried a different baud rate.

At first, it was 9600 transmission speed, but now it's normal at 115200. Is there a way to put it back? And what will happen if I don't put it back?

[Rich R · Accepted solution]

As soon as the AP starts powering up, enter the ESC key repetitively in the terminal window, until you see the u-boot prompt then:
u-boot> setenv baudrate 9600
## Switch baudrate to 9600 bps and press ENTER ...
u-boot> saveenv
Saving Environment to SPI Flash...
Erasing SPI flash...Writing to SPI flash...done
u-boot>reset
Change your terminal to 9600 and then press ENTER when it prompts you after changing the setting.