Possibly an idiotic question re Time Machine...

[JayM27]

I'm on Mavericks and am upgrading to Sierra as I'm about to buy a new audio interface (I use Logic X). Sierra will allow to still use existing audio plugins that I do need. Anyway, upon going to use Time Machine to backup before doing so, I rather impetuously got rid of previous backups that were there (simply by dragging them to the Trash). I've gone to backup now selecting the external drive and upon doing so, it presents me with a main option of using the Backup Disk(s) (which I named Touro S External) - essentially 800 GB being shown so the old backup is clearly still on there - or the name of the drive under Available Disks (Touro S) which is 1TB (and indicated as such). When I click on the Backup Disk, it only gives me the option to Remove, where clicking on Touro S gives me the prompt to Use Disk.

This is a bit confusing. Which should I be using?

I'm pretty clueless when it comes to these matters as you can see...

 

[warp9]

Did you empty the trash?

 

[chscag]

If you removed Time Machine backups by dragging them to the Trash, you destroyed the integrety of your backups. Time Machine backups must only be removed within Time Machine. Some of your old backups might still be useable but it's probably better to just start over with a new Time Machine backup.

Even if you didn't empty the Trash, you won't be able to "put back" the backups you removed. Time Machine works very differently than other backup software. Most folks who do backups religiously also use cloning software. Carbon Copy Cloner or SuperDuper.

 

[Fishrrman]

"This is a bit confusing. Which should I be using?"

Stop using tm and switch to either CarbonCopyCloner or SuperDuper.
Either is much better.