Maximum number of USB drives

Quote from Ghazzawi

any help ?

In order to anyone help you, that person would have to have the same or a similar setup you have.

I never saw anyone (on the forum threads) mentioning more than 4/5 drives on Pis.

And usually, those drives are connected with some kind of "special box" (ICYBOX, Fantec, Orico, etc) that has a proper controller chip (ASM, JMicron, Elan) that takes care of all the communication from the box to a SINGLE USB Bus.

Now, you want to have USB drives plugged to a Hub that you don't even mention which one but I only picture something "Alienexpress-like", low-budget without (probably) any proper controller.

How can anyone give you an answer?

Quote from Ghazzawi

please also note that if I install a fresh Debian 64 system on the SSD and use lsblk command , I can see all my 12 Disks ( 11x 4TB + 1x Root SSD)

however after in install OMV I start having the problem above

If you can see them all while having only RaspiOS 64 running (you say Debian but if it's a Pi, then you mean RaspiOS) does that mean that you can access them just the same?

Have you tried to use them without OMV, and see if the system doesn't crash?
Or you only ran lsblk and they show up?

What about lsusb -t? Do they show as indepent on the single BUS:

This is how it shows on a box with a proper controller (ASMedia 1053E) (The chip on this one is Via Labs VL817)

pi@xxxxxx:~ $ lsusb -t
/:  Bus 02.Port 1: Dev 1, Class=root_hub, Driver=xhci_hcd/4p, 5000M
    |__ Port 2: Dev 2, If 0, Class=Hub, Driver=hub/4p, 5000M
        |__ Port 1: Dev 5, If 0, Class=Mass Storage, Driver=uas, 5000M
        |__ Port 2: Dev 3, If 0, Class=Mass Storage, Driver=uas, 5000M
        |__ Port 3: Dev 6, If 0, Class=Mass Storage, Driver=uas, 5000M
        |__ Port 4: Dev 4, If 0, Class=Mass Storage, Driver=uas, 5000M

And another (ASMedia 1352R) with RAID capabilities:

pi@xxxxx:~ $ lsusb -t
/:  Bus 02.Port 1: Dev 1, Class=root_hub, Driver=xhci_hcd/4p, 5000M
    |__ Port 1: Dev 2, If 0, Class=Mass Storage, Driver=uas, 5000M
    |__ Port 2: Dev 3, If 0, Class=Mass Storage, Driver=uas, 5000M

Does your HUB shows the same type of info when ALL drives are working and not crashing?

This is only academical, but you are expecting the Pi to be a full fledged DATA CENTER and it's not.

Even if you manage to put them only recognized (doesn't matter if it's with OMV or not) you only have a single USB Bus to divide to ALL those drives. The bottleneck will be Humungous.

Well, didn't really answered but there's nothing to answer, really.

Good luck.