Time Machine B

chrisman9

macrumors member
Original poster
Nov 13, 2016
79
2
#1
HI-- Salvaged from my old PC Laptop, I have had an old 'spinning-kind' of external harddrive from which Ive retrieved some contents of the laptop to my iMac; it's called a 'Rosewill.' Im very unfamiliar with how these things work and, being simple and relatively fastidious, I would like to purge the harddrive then set it up to be backup for the iMac. My questions are: 1) how can I tell whether the Rosewill has already been saving my iMac activity? because I would not want to delete that. 2) Once purged, and starting fresh, how do I instruct the iMac to use the external harddrive for continuous backup from here on?

PS--I have consistently selected "decide later" when iMac asks if I want to use the external hard drive to back up Thanks for your Help
 

cruisin

macrumors 6502a
Apr 1, 2014
956
215
Canada
Disk Utility has erase options including secure erase settings.

Under Time Machine settings (System Preferences > Time Machine) it lists all drives used for backups. Unless you set up a backup, then it should be empty. Here you can also set a new backup.
 

chrisman9

macrumors member
Original poster
Nov 13, 2016
79
2
Disk Utility has erase options including secure erase settings.

Under Time Machine settings (System Preferences > Time Machine) it lists all drives used for backups. Unless you set up a backup, then it should be empty. Here you can also set a new backup.

to crusin: 1) where do I find 'disc utility' ?
 

cruisin

macrumors 6502a
Apr 1, 2014
956
215
Canada
to crusin: 1) where do I find 'disc utility' ?
It comes as part of macOS. It can be found with the rest of the applications (like Mail, Safari, Contacts) or in spotlight (the magnifying glass by the clock) by searching for Disk Utility (just typing the first few letters should show it within the first 5 results).
 

monokakata

macrumors 68000
May 8, 2008
1,864
383
Hilo, Hawai'i
"Rosewill" is the brand name of your enclosure. You should probably use Disk Utility to learn just what sort of disk is in that enclosure.
 

chrisman9

macrumors member
Original poster
Nov 13, 2016
79
2
to cruisin & monokakata: Thanks, Ive been able to open "disc utility" and can see the device (Rosewill) in some detail. when I click on the "erase" option at the top, I am asked to 1)enter a name // 2)choose a partition map and format What is the name for and how do I decide upon a "partition map and format" ? Thanks for your help
 

monokakata

macrumors 68000
May 8, 2008
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The name is your choice. As for what it's for -- really just for you to easily ID the disk when it appears in Finder or elsewhere. I'd suggest something with "TM" embedded in it, though, so the name itself will remind you what it is.

Then you want the partition to be Mac OS Extended (Journaled).
 

chrisman9

macrumors member
Original poster
Nov 13, 2016
79
2
to monokakata: Thanks for your reply and advising--the plot thickens, however (as usual)
I did erase the ancient data from the device (I named it Rosewill) AND formatted it according to your "Mac OS Extended (journaled)" then closed disc utility and reopened it to find all its' capacity (500.11GB) "used" ---the "use bar" is colored all yellow representing what is being called "other" (as opposed to apps, photos, audio, etc) For the record, my iMac harddrive(1TB) says that Ive only used 79 GB---and Ive not instructed Time Machine yet, to back up. What do you think has happened ? and what should I do? Im tempted to re-erase, but ask for counsel before winging it. Aloha
 

monokakata

macrumors 68000
May 8, 2008
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Hilo, Hawai'i
Which version of MacOS are you using?

Did you erase the disk using Disk Utility? Disk Utility has changed over the years. In the current version, you have to erase a disk before you can partition it. In the old versions, maybe not (can't remember).

If you erased Rosewill by using Finder, then try emptying the trash.
 

chrisman9

macrumors member
Original poster
Nov 13, 2016
79
2
to monokakata: Yes, I had opened Disc utility thru finder and have proceeded to empty the Trash. The 'yellow' has disappeared and it appears that Rosewill is empty too ! Can you instruct me now in how to ''set up" if that's the right word, Time Machine to back up all that Ive done thus far on this iMac (2 years worth) and to routinely save data ongoingly. Thanks.

oh for the record: O/S X El Capitan 10.11.6
 

monokakata

macrumors 68000
May 8, 2008
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Hilo, Hawai'i
Now you go to System Preferences, choose Time Machine, choose "Select Disk," select Rosewill, and you're done.

As many people have said in many threads, TM does sometimes screw things up. This has happened to me.

I'm going to change to CarbonCopyCloner when I get around to it.
 

chrisman9

macrumors member
Original poster
Nov 13, 2016
79
2
Thanks, monokakata. I will procede. Ive 'heard' others take issue with TM, but, as you can probably recognize, Im a relatively unsophistocated use and I will trust that at least now having some backup will yield benefit should the proverbial you-know-what hit the Fan one fine Day. Thanks much again, for your help---Aloha !