Drobo 5C / 5D and Big Sur issues + workarround

I got my share of Drobo issues this weekend. Upgraded a Mac mini 2014 to Big Sur 11.6.2 because the Drobo 5C would be supported. Did perform a firmware update and Dashboard update before the macOS update so all would be good. Turned out the answer is yes, but…

After booting the Drobo would mount on the desktop with a generic yellow icon. And the mini would be sloooooooooow. As in not usable for any tasks. In the end unplugged the Drobo and plugged it back in. The icon went back to normal and finally performance was good again.
Which probably means I will have to unplug / plug the Drobo on each reboot in the futuren. Which is not great as this is a server on a remote site where there is no direct access.

Next I tested a MacBook Pro that is on Big Sur 11.6.2 with a spare Drobo 5D. The same issue. A generic yellow icon when restarting the MacBook Pro, but luckily no performance issues. Drobo Dashboard however refuses to show the Drobo.
Unplugging and plugging resolves this.

Because I need a solution for my remote site I looked into a way to unplug without unplugging. That can be done using VMware Fusion. Just install that on your Mac and create a small virtual machine. Doesn’t matter what OS you use, so a small Linux will do. Start this virtual machine after a reboot of the Mac and then go to the settings for the VM. Select the USB ports and click the checkbox next to the Drobo to connect it to the virtual machine. This will “unplug” the Drobo from the Mac in software which has the same effect as unplugging it from the Mac. Next deselect the checkbox to release the Drobo. This will “plug” the Drobo back into the Mac. After this you can shutdown VMware Fusion.
The Drobo will now appear on the desktop with the default Drobo icon and the Drobo is available in the Dashboard again.