@beaglenz First of all welcome to the Rockstor community. Could you please post the output from the following 3 commands separately so that I can see how your external usb caddy is representing the disks within it. If you do the commands on the machine in the configuration that produces the serial warning that would be most helpful.
/usr/bin/lsblk -P -o NAME,MODEL,SERIAL,SIZE,TRAN,VENDOR,HCTL,TYPE,FSTYPE,LABEL,UUID
This is the command that Rockstor uses currently to see what’s what.
And also the following command would be helpful as well:
ls -la /dev/disk/by-id/
udevadm info --name sdX
where the sdX is a valid name for a drive in the caddy.
What would be great is if you could do this last command for 2 different drives in the caddy (when they are in at the same time), ie 2 drives in caddy and do the last command for each of their names as they appear in disks.
Also a screen grab of the Disk’s page would be great.
N.B. there may be concerns over publishing your drive serial numbers however all we need to see is if they are alike / unique or show up at all. Thanks. So you could obscure the beginning of them all if that worries you.
If you could surround the results with triple back single inverted commas in the forum posting it will help with formatting and readability. ie as I have done here with the commands.
Please also be aware that this kind of hw setup does rather circumvent many of the safeguards that are assumed though and a recent discussion on the linux-btrfs mailing list didn’t come out in favour for this kind of device (sorry bit pushed time wise to look it up and link but will try to do so later). I’m assuming, maybe rather prematurely, that this caddy has one usb cable and talks to all 4 drives through it. In that arrangement all 4 drives can disappear in one go simply through a usb reset so isn’t at all robust from a hardware perspective, or from a btrfs perspective as momentarily all drives will be lost at once. Especially given usb resets are not rare.
Glad you like Rockstor and lets hope we can accommodate you, even given the questions over the hw arrangement.