How to Update the Firmware on Problematic Bitmain Antminer E3 Miners

Last month Bitmain has released an updated firmware for their Antminer E3 miners to extend their life for mining Ethereum Classic (ETC) and Ethereum (ETH) with the approach of 4GB DAG sizes, however a lot of users had issues updating all devices successfully. Errors preventing the proper update to the fixed firmware such as:

413 - Request Entity Too Large

or

mount: mounting ubi1:rootfs on /mnt/config failed: Invalid argument mkdir: can't create directory '/mnt/config/home/usr_config': No such file or directory cp: can't create '/mnt/config/home/usr_config/': No such file or directory umount: can't umount /mnt/config: Invalid argument mount: mounting ubi1:rootfs on /mnt/upgrade failed: No such file or directory runme.sh: cd: line 122: can't cd to /mnt/upgrade/upgrade umount: can't umount /mnt/upgrade: No such file or directory

The easiest method we have found that works 100% in a couple of Antminer E3 miners that we had issues updating remotely via the web interface of the devices is to flash the SD card recovery firmware and then update normally with the latest fixed firmware. The only drawback for this method is that you need to have physical access to the E3 miners as you cannot do the SD card recovery procedure remotely unfortunately.

Here is a quick guide on how to updated problematic E3 miners:
– Download the E3-SD-20180806-pool.zip SD card recovery firmware file from Bitman
– Have a handy 4-8GB micro-SD flash card (larger capacity should work but is not needed), format it with FAT32 file system and extract the contents of the E3-SD-20180806-pool.zip archive on the card
– Insert the SD card into the slot at the back of the Antminer E3 device (it should be powered off)
– You need to open the control board of the miner and switch the position of the jumper labeled JP4 and then power on the device
– Wait for about a minute until you see the red and green LEDs on the control board start blinking together
– Power down the Antminer S3, revert the position of the JP4 jumper to its original place, remove the SD card and insert the control board back on its place
– Power on the miner, wait for it to boot (it will have the default configuration settings) and go to Upgrade to flash the latest fixed firmware
– You can download the latest fixed firmware for Antminer E3 here – E3_V540_0327.tar.gz
– Wait for the flash procedure to finish and the miner to reboot, set your mining pool and wallet address in the configuration settings and you should be ready to mine normally once again until the DAG size for ETH and ETC reaches very close to 4GB that is…