Disk Not Ejected Properly alert

[midilance]

I recently purchased a LaCie 6TBl USB3 external HD to use as Time Machine backup. I leave the drive on all the time. When I walk away from the computer for a while and then come back and wake it up I find at least one of these alerts at the top left of my desktop. The alert says: Disk Not Ejected Properly. Eject "LaCie D2 6TB Drive" before disconnecting or turning it off. This is a pain (constantly having to delete these prompts. I am also wondering what this might be doing to my new LaCie drive. I contacted Applecare and they suggested that I reinstall my system (El Cap). I reinstalled to no avail. Anyone having this problem?

[cuttime]

Do you have "Put Hard Disks to Sleep When Possible" checked in your Energy Saver preferences? Get ready for a flood of posts telling you to not let your computer sleep!

[mikehalloran]

Do you have "Put Hard Disks to Sleep When Possible" checked in your Energy Saver preferences? Get ready for a flood of posts telling you to not let your computer sleep!

Yep.

Since Time Machine is the app, my usual recommendations for using wireless or ethernet for Time Machine apply.

That 6T drive can be thrown into a Apple Time Capsule pancake (not tower) or a WD My Cloud Mirror—either are very easy to set up for Time Capsule.
https://mycloud.com/#/

I am recommending the My Cloud Mirror of late because it can hold multiple drives & it's easy to change them (lift a lid, single screw holds bracket). The Mirror can be found empty or loaded—the model is the sum of both/all drives (A Mirror 2G comes with a pair of 1G drives). Setting up for JBOD to alternate drives is not well explained but doable (and not an issue if the box has only one drive.