Cant see My 5D After Update with thunderbolt

I updated to 10.15.4 and now I cant see my 5D, I do see my 5D3 But not my original 5D.
Yes I updated the dashboard… Any suggestions ?

ALSO - USB3 works but I cant see the drabs using thunderbolt

Can you confirm what ports you were using for each Drobo initially?
It is correct that you cannot get either Drobo recognised via Thunderbolt after your Mac upgrade, or just one Drobo?
And can you ‘see’ both Drobos using USB?

I was using the Thunderbolt 1 ports on both drobo 5D initially. I cant see any of the drabs with the new update while connected through thunderbolt 1. I can see them if I use the USB3 port.
My Drobo 5D3 connected using USB C works fine.

Please advise

I’m a little confused on your reference to Thunderbolt 1, USB and USB-C ports - what Mac are you using? Can you post a photo of your Mac’s port connections?

Im using a 5k iMac. Im using a thunderbolt adapter to usb c

Drobo 1 connected to Drobo 2 using thunderbolt then into the adapter then into the Mac. - Didnt work after update.

I tried drobo connecting directly into adapter into usb c - dint work

It only works with usb 3 directly into computer now…

OK thanks.

This is an Apple issue and not a Drobo issue as a result of the Catalina update (10.15.4) on some Macs. On the Apple support blogs, other users have experienced similar power drop-outs on their USB-C port after the same upgrade, resulting in connected monitors no longer working and the like. I suggest you register your issue now with Apple.

As you have already proven, your Drobos still work on your USB-3 ports, and for the time being, connecting them there will enable you to continue your access to your data, until a future Apple update resolves their USB-C issue.

Another reason for me to wait out any upgrade to Catalina.

EDIT: I understand Apple has recently released a supplementary update to 10.15.4 which reportedly includes a fix which “Resolves an issue where a USB-C port in your Mac may become unresponsive”. It would be good to know if this supplementary update resolves your issue?