How to recover wall ap firmware under boot ?

For wall ap, the guide to recover firmware is shown as below:

I. Network Topology

                                             

II. Requirements

1. Generally, we recover firmware under BOOT mode if we deletes firmware on Main Mode by mistake, firmware broken or any other unknown reasons that devices cannot boot up and enter Main Mode.

2. Finish reading Device Management --> System Management & --> Firmware Upgrade, have knowledge of how to transfer firmware with TFTP server.

3. Disable firewall on your PC.

III. Configuration Steps

1.      Open Wireshark, load a packet capture process as below.  AP 192.168.64.64 lost firmware and is requesting 192.168.64.1 for firmware.

2.  Assign IP address 192.168.64.1 to laptop, enable TFTP Server and also prepare the firmware, the firmware put on same folder with tftp server.

2.      Edit a notepad name as "FileList.txt", put it in the same folder as shown above,   the content is the firmware name you're going to transfer

4. AP will begin downloading firmware soon, verify by viewing TFTP Server connection status.

5. AP will reload when finish recovering firmware

IV. Verification

Login AP via telnet and AP is recovered.