I’ve got my MBP connected via USB C to the LG 27UK850 display and I was hoping I’d be able to have a USB drive always plugged into the back of the display that would back up to Backblaze.
This works in practice but every time the MBP goes to sleep I get a ‘Disk not ejected properly’ message. I dismiss and after a few moments the HD mounts again.
Is there anyway around this? Or should I just not worry about it?
I just installed an app called Mountain that deals with this, but I am only 2 days in so can’t fully endorse it.
I use it with a JetDrive Lite in my MBP, but I think it also handles USB drives. It unmounts drives when the Mac sleeps, then remounts them when waking.
Doesn’t sound like it was resolved 
Thanks! I’ll have a look into Mountain.
It’s worth noting that I don’t think Mountain has been updated in quite some time (their website reads “Ready for macOS High Sierra”) and may not be fully compatible with Mojave. I’ve tried reaching out to the developer for clarification but didn’t get a response.
I have a Mountain license and have enjoyed using it in the past, but have decided to discontinue my use of this app until it gets updated.
I’ve been using Mountain on Mojave without any issues on both my MacBook Pro and my new Mac mini.
Good to hear that it’s been working well for you under Mojave. Though, I’m still a little leery of using a system-level app that doesn’t officially support Mojave.
Yes - stay away from using an LG monitor for any hard drives plugged in! 
I have been a happy camper since …
Mountain on Mojave works great for me too (FWIW)
Is this just an LG monitor thing or a problem with any Monitor / ext HDD setup?
I’ve been using hard drives connected to the USB hubs built into Dell P2415Q monitors for a couple of years with no issues.
Is there any setup where I can still take advantage of the one USB C cable into the MBP but still have two external drives connected so they are backed up via Backblaze?
Rather than connecting to the monitor directly you could find a USB-C (or Thunderbolt 3) hub that has power pass through and hang the monitor and drives off of that.
That’s my setup. I have 2 external HDs and a Dell monitor plugged into a hub, then the USB-C cable from the hub into my MBP. Backblaze backs up everything.
That sounds like a plan! Any recommendations for hubs with power pass through?
Thanks!