I have an Atolla powered USB hub
https://www.amazon.co.uk/gp/product/B07B2HJG8P/ref=ppx_yo_dt_b_asin_title_o03_s
01
which I bought to power a spinning HDD that I plugged into my Pi 3B+.

I'm now using it in my Pi 4B. If the Pi is rebooted without shutdown and
power-off/on, it boots fine. However if it is shutdown and then the power is
removed and replaced (whether that is immediately or half an hour later) the
Pi refuses to boot: the green LED does not come on and nothing appears on
either HDMI output. If it is in that state and I unplug the hub, booting
continues immediately, even if the hub is replaced immediately after being
removed.

Has anyone some across this incompatibility? It's a bit of a bummer because
it means the Pi will not auto-start in the even of a power-cut - unless I am
present to remove/replace the hub.

It is related to the hub rather than what is plugged into it. It happens
even if the HDD and other devices are removed from it. Removing the power to
the hub is sufficient to allow booting: maybe I need some means of making
the mains to the hub delay coming on for a few seconds after power it
supplied to the Pi!

I'm wondering whether to buy a different make of hub, or whether I may find
that this is affected in the same way.

Does anyone know of a make of powered USB3 hub which is known to work with
the Pi 4 after power-cycle?



This is separate to the /etc/fstab auto-mount problem that I posted about
yesterday. In that case, the Pi would *start* to boot and then fail at mount
time; in this case there is no sign that the Pi is even beginning to boot.

--- SoupGate-Win32 v1.05