Should the hard drive for time machine back up go in to sleep mode when the iMac does ?
Yes, the Time Machine drives connected to my Mac's sleep when the computer's sleep. However, they do not sleep if only the display is sleeping.
How are you activating Computer Sleep?
(auto sleep or from the drop down menu)
If your are using auto sleep,
go to Apple > System Preferences > Energy Saver > click on the Schedule.... box and recheck the auto sleep settings.
If you are using the drop down menu and/or auto sleep,
go to Apple > System Preferences > Energy Saver and see if "Put hard disks to sleep when possible" is checked or unchecked.
Lastly, if you think that your iMac is not going into computer sleep mode or acting wonky.
Reset the SMC, as per > How to reset the System Management Controller (SMC) on your Mac - Apple Support and then re-test the sleep functions of the computer and external drive.
I am using a WD external hard drive for my time Time Machine. When I turn off the iMac the WD turns off also but when the iMac internal hard drive goes into sleep mode the WD stays on, using High Sierra . Any suggestions ? Thanks for responding
The computer is on auto sleep mode. And the computer is going into sleep mode but the external hard drive isn't.
The WD hard drive is about 10 years old maybe it is the problem. You have any suggestions on what type of new external hard drive to get for a 2010 iMac.
Personally I liked those older Passports and still have a few around that I use for redundant backups.
If you have to go cheap? The newer Seagate slim drives seem to be more reliable than the newer WD passports, including the MyBooks models that were nice to look at.
If you are in the market for a decent and reliable external drive?
It's wiser to get a multi-port OWC Mercury, that works with both older and newer Mac's.
see > https://eshop.macsales.com/shop/external-storage#interface-ports:usb-3-0-usb-3-1-gen-1
Should the hard drive for time machine back up go in to sleep mode when the iMac does ?
