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The infamous USB 3.0 issue - OK on stock vs. NOT ok on Merlin

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loveleeyoungae

Regular Contributor
EDIT 11th Dec: However, today I tried flashing older stock and Merlin firmwares, 3 versions of each type, all are 384 codebase. And I can now confirm that the issue is only on Merlin firmwares.

There's this infamous issue of USB sticks plugged in USB 3.0 port that has been mentioned here many times: When a USB stick is not detected, it is tricky to make the router detect it again. A normal procedure of rebooting router/re-plugging the USB stick wouldn't work. Even when everything is working normally, a normal reboot will always make the USB stick undetected. No icon in the Network Map webgui, not listed in the fdisk -l command in terminal. The only method is:
a. Power off the router and unplug the USB stick
b. Power on the router and wait for it to boot completely
c. Plug the USB stick
EDIT: Forgot to mention, changing to USB 2.0 mode/port also works, obviously.

My experience with this issue has been with Merlin 384.x versions, never had the chance to try on stock firmwares or 380.xx versions. So, as the new stock firmware 45149 was released several days ago, I thought of trying that. And it turned out my USB stick was always detected properly on this firmware, always showed up after every reboot. I then tried with 384.8_2, and the issue came back. So:

1. Is it reasonable to say that the issue is only in Merlin fw and should we suggest RMerlin to have a look at it?

2. My "My Passport Ultra" Western Digital portable hdd has always been detected properly (even with add-ons installed - entware, Diversion etc...), which made me think the issue only occurs with USB sticks/flash drives? My USB stick is a SanDisk Ultra Flair USB 3.0 Flash Drive.

EDIT: I've just read the thread talking about unmounting script doesn't work properly which may be related to this issue. However, for the tests, I didn't install anything on the USB stick, and the router was always flashed and reset to defaults.
 
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The only method is:
a. Power off the router and unplug the USB stick
b. Power on the router and wait for it to boot completely
c. Plug the USB stick

Is this the only way you’ve gotten your HDD to work in usb 3.0 mode? Mine only works when the USB 3.0 plug is switched to USB 2.0 mode, or if I use the USB 2.0 plug on the back of the router (ac-3100). Used to work fine in USB 3.0 mode since about 384.6 then everything went to hell, just recently got the router to finally mount the USB again.
 
Is this the only way you’ve gotten your HDD to work in usb 3.0 mode? Mine only works when the USB 3.0 plug is switched to USB 2.0 mode, or if I use the USB 2.0 plug on the back of the router (ac-3100). Used to work fine in USB 3.0 mode since about 384.6 then everything went to hell, just recently got the router to finally mount the USB again.
No, actually my HDD (Western Digital "My Passport Ultra") has always been working fine.
The one got issue is the usb stick/flash drive (Sandisk Ultra Flair).
And yeah, I forgot to mention what I thought it was obvious: changing to usb 2.0 mode/port works. Just updated my first post, thanks.
 
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No, actually my HDD (Western Digital "My Passport Ultra") has always been working fine.
The one got issue is the usb stick/flash drive (Sandisk Ultra Flair).
And yeah, I forgot to mention what I thought it was obvious: changing to usb 2.0 mode/port works. Just updated my first post, thanks.
Ahh, I see. I’m the opposite my 5tb Seagate drive won’t show up on 3.0 mode, but a small capacity USB stick will show up just fine. Hopefully there’s a fix for this cause I’ve tried everything.
 
That stock firmware is newer than the latest Merlin. So have patience, and once Asus release the GPL source, work can be scheduled for a Merlin release.

https://www.snbforums.com/threads/merlin-please-update-rt-ac86u-binary-3-0-0-4-384_45149.50323/
Thanks for your comment. Yeah, I know the rules and faqs on this forum, so obviously I didn't ask about Merlin update.

I just felt that the issue was only on Merlin fw, but as my test was limited, I didn't have data to confirm that. Thus this thread.

However, today I tried flashing older stock and Merlin firmwares, 3 versions of each type, all are 384 codebase. And I can now confirm that the issue is only on Merlin firmwares.

So, I think this might be considered "bug". If it's not, I'm sorry. But I hope it's fine to tag you here, @RMerlin .
 
As an update, Merlin's Alpha build 284.9_alpha 1 seems to have resolved this. There is a new option "Added USB3.0/2.0 mode switch setting in Administration --> System --> USB Settings." Enabling it on this new menu option resolved it, my USB is working as a v3 device again.
 
As an update, Merlin's Alpha build 284.9_alpha 1 seems to have resolved this. There is a new option "Added USB3.0/2.0 mode switch setting in Administration --> System --> USB Settings." Enabling it on this new menu option resolved it, my USB is working as a v3 device again.
that option has been there for quite a while. Switching the usb 3.0 port to 'usb 2.0' mode makes the port act as a 2.0 port. That maybe how yours began to work. Try keeping it in usb 3.0 mode and see if it still works. The update didn't fix it for me.
 
Using Sandisk Ultra connected to USB3 port of RT-AC88U which was previously on 'usb 2.0' mode.
After update to 384.9 the above works using 'usb 3.0' mode.
 
Sorry for reviving old thread. I am having similar issue with Sandisk usb 3.2 plugged into usb 3.0 port on Asus AC-RT68U running asuswrt-merlin 386.5_2. Usb will work fine for awhile, then it ghosts & I have to reboot router to get the usb icon back. This is problematic as I am using amtm & custom scripts. What are my options?
 
Don't use USB 3.0 mode. Use another (make) USB drive.

The best option is to use a UGreen enclosure (or similar) with an SSD instead.
 
Sorry for reviving old thread. I am having similar issue with Sandisk usb 3.2 plugged into usb 3.0 port on Asus AC-RT68U running asuswrt-merlin 386.5_2. Usb will work fine for awhile, then it ghosts & I have to reboot router to get the usb icon back. This is problematic as I am using amtm & custom scripts. What are my options?
Your symptoms don't sound the same as those discussed in this thread. Does your device work OK in USB2 mode? Look for errors in the router's System Log.
 

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