[raywan]

USG-Pro-4 security gateway reached end of life means no new firmware update support forever.However, I found that DDWRT still supporting USG-Pro-4 for a long periodic of time but seems no one using that and no discussion in this forum.
My question is that how to flash ugw4-e220.image to USG-Pro-4 a new USB flash driver without destroying original internal USB flash driver but i don't know how to do that.
Is there any people give me a hints about that?

https://download1.dd-wrt.com/dd-wrtv2/downloads/betas/2024/01-02-2024-r54682/ubnt-unifi-ugw4-usbboot/
I only find these 2 files but don't know how to make use that. Thanks you very much.

[kernel-panic69]

Thanks for posting this. It appears that support was added in 06-01-2018-r36079 without much fanfare. I can only suspect that you can use ImageUSB or rufus to create a bootable USB stick using those images, but I do not have this device in hand to confirm, so Caveat Emptor. At least you will have the original USB drive to recover with if you use a new USB drive. I found mixed reviews of using EMRK, so that is not advisable.

[raywan]

Thanks for your kindly reply. I tried flash with the image to external usb driver then plugged it into USGW4 without any help. It won't boot anything if usb was plugged. Then i discovered that it requires Console cable to make it works.

https://openwrt.org/inbox/toh/ubiquiti/ubiquiti_unifi_security_gateway_pro_4?s[]=usg&s[]=pro&s[]=4

Try to get back to you if the console cable arrived. I will leave some commend here if i can successfully flash the DDWRT into USGW4.

[kernel-panic69]

Thanks for the update and feedback. Please let us know if it's working on current release: https://download1.dd-wrt.com/dd-wrtv2/downloads/betas/2024/01-12-2024-r54905/

[raywan]

I flashed the most updated ugw4-e220.image to USB then using "fatload usb 0:1 vmlinux.64" command to load the vmlinux.64 to usg-pro-4 memory.
My question is that how to boot vmlinux.64 in the memory? I am not familiar with u-boot environment. Am i doing wrong?
I try to refer openwrt firmware flash procedure. Openwrt firmware seems packing everything into a openwrt-19.07.4-octeon-er-initramfs-kernel.bin then boot up automatically.
Is there anyone know how to flash/boot ugw4-e220.image from USB flash drive?
Thank you very much.