Openwrt RPi4 USB boot

Just a quick question for you guys in the know... Now the RPi4 has had it's official update for USB booting added to it's eeprom, does that mean when I compile my next firmware, instead of using etcher to create a sd card, I can use a USB stick instead?

Without testing it: With Raspberry OS I had to burn the image to the SD card first, then booting up and activate usb boot through raspi-config before an USB device booted. The Rpi4 was bought in 09/2020. With the initial boot of Raspberry OS it updates the eeprom. After the update USB boot should work even with OpenWRT.

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My eeprom is already updated, And has usb boot enabled... So I'll give it a try with Openwrt and see what happens.

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what is the major benefit of booting openwrt from usb, pls? (bit faster booting perhaps, I prefer booting frm sd and use external usb for docker, lxc or else requires more space than usual).

Booting OpenWrt from USB works fine though it does require changing the root filesystem device in the command line in the boot directory. Otherwise the rootfs won't mount on the USB.

I don't use usb for anything other than the Ethernet dongle... Although I have thought about putting a little SSD with it and using it for transmission...

The major benefit of booting OpenWrt from USB using NVMe SSD in a USB 3 enclosure is noticeably faster boot speeds and a much more reliable file system as microSD storage is notoriously unreliable with primitive bad block management, while NVMe SSD is highly reliable with sophisticated bad block and garbage collection management. The write cycles allowed on NVMe SSD is far more than microSD would ever allow, making microSD life span that much shorter and prone to failure.

If it's about reliability only, NVMe USB boot wins hands down, the serious speed gain is a welcome added bonus.

For a security point of view I not recommend running torrent client on router. Better get a RPI with rtorrent. Every device should have the job it does best.

Did you ever get OpenWRT booting from USB on your Rpi4? I was able to get USB boot to work via Raspbian on my Rpi4, but could never get OpenWRT to work. So I had to stick with booting from an sdcard. And of course, had some bad blocks on said card, ended up having to get a new one, and reflash from scratch. It would sure be nice to use a USB stick or other USB storage device so that I don't have to have sdcards failing all the time...

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Yup, same here. Tried everything apart from building it from scratch (which probably is the only way this will work). I have the ASMT2115 SATA/USB3.0 that works on UASP. I believe the bootloader has support for it, because raspberry pi os, ubuntu server 21.04, and manjaro minimal boot perfectly fine with the adaptor.