I have a USB, I believe it is a USB 3 device, that works nicely with my OpenWRT router after the router has booted. So I moved to use the device for extroot. However, I found the device simply won't power up during boot.
The device is a USB SATA box, with an SSD inside, and it has a power and activity LED. By won't power up, I mean the LED has no signal at all, like not powered up. However, when I unplug the device, I got a disconnected message in the log. Then, if I plug it back, it works nicely again.
I am on OpenWrt 19.07.3 r11063-85e04e9f46. I found a similar post, but it doesn't solve my problem and is closed.
This is probably a current/power issue. Especially on powering on the router needs the power what it is getting from the PSU for itself. So not much left for other devices (same is counting for the SSD also). If the router is running the router is using less power and its working. In general a router is not designed to give a lot of power over USB3. You have to use a extra PSU for your drive. It might be possible to use a SSD with lower power consumption also.
I had a look into this thread before and I thought the Bug was before 19.xx. The threadstarter is using 19.07.3 already.
But I know a lot of devices which have issues with power consumption especially on boot.
Personally I have here still a RPi3 with a 60GB SDD (USB3 interface) connected. It isn't correctly recognized on boot. With PSU for the SSD no problem. It can be a controller issue also either on SSD itself or the controller on case for the SSD. Both is possible.