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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For accessing the flash-tool (or flash-tool2) you have to reboot in update mode.
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