How to flash a WRT-compatible router with a new OpenWRT image
There are two types of image files that you can download. One is type .bin and the other is type .trx. If you are flashing from the manufacturer's web GUI interface, you should use the .bin image file. If you are flashing from the OpenWRT web GUI interface, you should use the .trx image file. If you are flashing from the OpenWRT shell, use the .trx image file.
Suppose your new image is located in /tmp/linux.trx of your OpenWRT file system. From the OpenWRT command line, issue the following command to flash the device with the new image.