If for some reason there is a problem with the firmware update, some newer firmwares now have an alternative way to update the firmware. Additionally there is a package available, which injects the flash-tool2 into the existing firmware (flash-tool2).
With this alternative method a downgrade to older versions is possible too. We recommend downloading a backup of the configuration before attempting to flash the firmware.
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To use this firmware flashing tool, you need a firmware version equal or higher than the ones listed above.
Newer versions:
For accessing the flash-tool (or flash-tool2 if installed via the ddflash 2 package) you have to reboot in update mode.
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Change the URL in the address bar to contain flash-tool.php (or flash-tool2.php) instead of update-tool.php
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