Use Time Machine on an external HD to back up multiple computers
I keep searching the community but I can't find the answer to my question. So here goes. I have a Mac Mini M1 running Big Sur and a MacBook Pro running Big Sur. The external HD is connected to the Mac Mini M1 and is currently taking care of Time Machine just fine. So now I'd like to use that HD to back up my Macbook pro as well. I can connect the two computers but I can't gain access to the Mac Mini M1 with Time Machine. I set up file sharing on the Mac Mini M1 with Time Machine in the shared folders. Under users, it's set to read-write. Then on my MacBook Pro when I connect to the Mac Mini M1 I can select Time Machine but I get an error message: There was a problem connecting to the server "xxx.xxx.x.x." You do not have permission to access this server.