Delayed problem after firmware update

[David Arnstein]

I have an RT-AC68P and an RT-AC68U in different locations. I have been flashing both of them with updated Merlin images as soon as they are published. I do not do any extra work on either router, such as clearing out user settings. I just flash the .trx file and wait for the router to reboot.

The -68P gives me no problems.

The -68U reboots and gives 100% good service. But at some time during the night, it stops. I cannot ping the router, and so obviously I cannot access the router via ssh or https. So I power-cycle the router. After that, the router gives me no problems until the next image update from Merlin.

These two behaviors have been 100% consistent since at least version 384.6. This is not a show-stopper type bug but it is interesting.

 

[RMerlin]

Flashing is never a 100% foolproof process (except on the RT-AC86U), because you are flashing on top of a running image. Asus tries to prevent issues on the subsequent reboot by having a temporary filesystem in RAM, but that doesn't work 100% of the time, and sometimes a manual power cycle is required to complete the post-upgrade reboot.

For some unknown reason, the RT-AC68U is more prone to this problem than other models. Could be just a coincidence with the size of the firmware and the physical location of each files within that image.

The RT-AC86U is an exception because it has two firmware images, allowing it to flash one while running from the second one.