Watch the TFTP server logs. If you see “Timeout,” check your firewall and cable.
Important Firmware Update for Your FiberHome AN5506-04-F Device An5506-04-f Firmware Update
Yes, using the same methods, but only if the bootloader’s NVRAM flag allows it. Some revisions contain an anti-rollback fuse (e.g., efuse set), making downgrade impossible. Watch the TFTP server logs