Help! I relocated my Drobo and now Time Machine doesn't see the backup.
As the title says, I unplugged the ethernet cable for my Drobo B810n from the back of my computer and plugged it into my Time Capsule. When I view the Time Machine preferences, the computer is ready to back up my files to the Drobo just like before but it says that there is no old backup! How do I get Time Machine to recognize the current backup again?
I'm not sure I am getting this right, but if you had the Drobo directly connected to your mac and now it is connected via ethernet, then the time machine back-up formats will be different. NAS backups via Time Machine use a "disk image" and the connection is over the network protocol SMB, while locally connected drives just mount the drive and use HFS or the more modern APFS format. As far as I know you can't get Time Machine to use regular format over a network connection.
Some information is here: < https://support.apple.com/guide/mac-help/types-of-disks-you-can-use-with-time-machine-mh15139/11.0/mac/11.0>
If you mount your Drobo directly, I think you will see the files again.
This is not quite what you said in your message (you say you previously had and ethernet cable between the drobo and mac), so I might be misinterpreting things.