Just dug out my old EA4500 with 21.02 and tried to upgrade to latest, encountered the message about incompatible flash layout as discussed here. I had no trouble changing the nandboot and altnandboot parameters as instructed; they now show the intended 0x400000 as the third read.e parameter ...
nandboot=nand read.e 0x2000000 0x200000 0x400000; setenv bootargs $(console) $(mtdparts) $(fs_bootargs_root) serial_number=$(sn) uuid=$(uuid) hw_version=$(hw) device_mac=$(mac) factory_date=$(date) wps_pin=$(wps); bootm 0x2000000;
altnandboot=nand read.e 0x2000000 0x1c00000 0x400000; setenv bootargs $(console) $(mtdparts) $(alt_fs_bootargs_root) serial_number=$(sn) uuid=$(uuid) hw_version=$(hw) device_mac=$(mac) factory_date=$(date) wps_pin=$(wps); bootm 0x2000000;
... but flashing the factory image just doesn't seem to be working. From a SSH terminal I get kicked off as soon as executing the command, and the router just sits there with its LED slowly pulsing and seemingly never completing the flash write.
root@OpenWrt:/tmp# sysupgrade -F -n ./openwrt-24.10.1-kirkwood-generic-linksys_ea4500-squashfs-factory.bin
Wed May 28 09:38:08 UTC 2025 upgrade: Image metadata not present
Image check failed but --force given - will update anyway!
Wed May 28 09:38:08 UTC 2025 upgrade: Commencing upgrade. Closing all shell sessions.
Connection to 192.168.1.1 closed by remote host.
Connection to 192.168.1.1 closed.
After 30 minutes I gave up, and after a few failed boots got it to boot into the recovery partition. Confirmed that the nandboot/altnandboot parameters were still correct then attempted to flash the factory firmware from LUCI. Again, slow pulsing LED for 30 minutes then I gave up.
Anyone know what's going on here, how I'm supposed to do this?