Updated RT-AC68U to Merlin 386.5 and lost USB drive support


Occasional Visitor
I just updated Merlin on my RT-AC68U from version 384.6 to 386.5 and immediately noticed that my USB NFS shares had disappeared. I reverted back to 384.6 which brought a host of problems since I lost the ability to log in to the router (kept telling me the password was wrong) so I had to factory reset and enter everything from scratch again, but the attached USB drives were still not visible. Went back the 386.5 again, removed all USB drives, cleared the system log, and rebooted the router again. After it restarted I connected one of the drives and watched the log, which showed the attempt to mount the drive. Hoping that someone can help me fix this if I post the system log here. At the end you can see multiple attempts to reset the drive but then it says...

kernel: scsi 1:0:0:0: Device offlined - not ready after error recovery

The same thing happens for any USB drive I plug in, both to the USB2 and USB3 ports. I'm running the router in AP mode. Has anyone got any ideas? Thanks.

EDIT: Just noticed that the RT-AC68U CPU is reported running at 93°C, which seems way too high.


  • syslog.txt
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Part of the Furniture
EDIT: Just noticed that the RT-AC68U CPU is reported running at 93°C, which seems way too high.
That's fairly normal for the RT-AC68U. My RT-AC68U ran at that temperature for the 5 years I was using it.

The syslog suggests there is a physical problem with the drive or the connection to it. There's nothing to indicate that it's getting as far as attempting to mount the drive as it is failing to bring to USB device online.
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Regular Contributor
My RT-AC68u runs at 76c. No fans or any active cooling.

The cpu can take it but the surround chips and solder points might not. I like all cpus to be under 80c if possible. 90c will shorten the life no question. I know the cpu can take higher temps but other things on the motherboard near it take some of that heat too.

I have a 86u that runs hot and added twin usb cooling fans to take it down to 68c from 90c. Just used a huge rubber band to mount them. EZ.

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